Method and apparatus for configuring network connection in mobile communication system

ABSTRACT

Provided is a method, performed by a user equipment (UE), of controlling an access, the method including receiving, through system information from a base station, barring information including a barring configuration information list and a public land mobile network (PLMN)-specific barring information list, the barring configuration information list including at least one barring configuration information and the PLMN-specific barring information list including at least one barring information per PLMN and performing a barring check based on the received barring information when the access is triggered, in which the barring configuration information corresponds to one barring configuration information index according to an order of being included to the barring configuration information list.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based on and claims priority under 35 U.S.C. § 119to Korean Patent Application No. 10-2018-0093375, filed on Aug. 9, 2018,in the Korean Intellectual Property Office, the disclosure of which isincorporated by reference herein in its entirety.

BACKGROUND 1. Field

The disclosure relates to a method and apparatus for configuring anetwork connection in a mobile communication system.

2. Description of the Related Art

To meet the soaring demand with respect to wireless data traffic becausethe commercialization of 4^(th)-generation (4G) communication systems,efforts have been made to develop improved 5^(th)-generation (5G)communication systems or pre-5G communication systems. For this reason,5G communication systems or pre-5G communication systems are alsoreferred to as a beyond-4G-network communication systems or a post-longterm evolution (LTE) systems. The 5G communication system prescribed inthe 3^(rd) Generation Partnership Project (3GPP) is called a new radio(NR) system. For higher data transmission rates, the implementation of5G communication systems on ultra-high frequency bands (mmWave), e.g.,60 GHz, is being considered. In 5G communication systems, beamforming,massive multi-input multi-output (MIMO), full dimensional MIMO(FD-MIMO), an array antenna, analog beamforming, and large-scale antennatechnologies have been discussed as ways of alleviating propagation pathloss and increasing propagation distances in ultra-high frequency bands,and have also been applied to NR systems. For system networkimprovement, in 5G communication systems, technologies such as evolvedsmall cell, advanced small cell, cloud Radio Access Network (RAN),ultra-dense network, Device to Device (D2D) communication, wirelessbackhaul, moving network, cooperative communication, CoordinatedMulti-Points (CoMPs), and interference cancellation have been developed.In a 5G system, Advanced Coding Modulation (ACM) schemes includinghybrid Frequency-Shift Keying (FSK) and Quadrature Amplitude Modulation(QAM) Modulation (FQAM) and Sliding Window Superposition Coding (SWSC),and advanced access schemes including Filter Bank Multi Carrier (FBMC),Non-Orthogonal Multiple Access (NOMA), and Sparse Code Multiple Access(SCMA) have been developed.

The Internet, which is a human-oriented connectivity network wherehumans generate and consume information, is now evolving into theInternet of Things (IoT), where distributed entities, such as objects,exchange and process information. The Internet of Everything (IoE) hasalso emerged, which is a combination of IoT technology and Big Dataprocessing technology through connection with a cloud server, etc. Inorder to implement IoT, technological elements, such as sensingtechnology, wired/wireless communication and network infrastructure,service interface technology, and security technology, are required, andin this regard, technologies such as sensor networks, machine to machine(M2M), machine-type communication (MTC), and so forth have recently beenresearched for connection between things. Such an IoT environment mayprovide intelligent Internet technology (IT) services that create newvalue to human life by collecting and analyzing data generated amongconnected things. IoT may be applied to a variety of fields includingsmart homes, smart buildings, smart cities, smart cars or connectedcars, smart grids, health care, smart appliances, advanced medicalservices, and so forth through convergence and combination betweenexisting information technology (IT) and various industries.

Thus, various attempts have been made to apply 5G communication systemsto IoT networks. For example, 5G communication, such as sensor networks,M2M, MTC, etc., has been implemented by a scheme such as beamforming,MIMO, an array antenna, and so forth. The application of cloud RAN as aBig Data processing technology may also be an example of the convergenceof 5G technology and IoT technology.

As described above, various services may be provided as mobilecommunication systems develop, and accordingly, ways of effectivelyproviding such services are required.

SUMMARY

Disclosed embodiments of the disclosure provide a method and apparatusfor effectively providing a service in a mobile communication system.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments of the disclosure.

According to an aspect of the disclosure, a method, performed by a userequipment (UE), of controlling an access includes receiving, throughsystem information from a base station, barring information including abarring configuration information list and a public land mobilenetwork(PLMN)-specific barring information list, the barringconfiguration information list including at least one barringconfiguration information and the PLMN-specific barring information listincluding at least one barring information per PLMN and performingbarring check based on the received barring information when the accessis triggered, in which the barring configuration information correspondsto one barring configuration information index according to an order ofbeing included in the barring configuration information list.

According to an embodiment of the disclosure, the barring informationper PLMN may include a PLMN identification (ID) index and barring listtype information, and the performing of the barring check may include inresponse to the barring list type information indicating an implicitbarring list, performing the barring check based on barringconfiguration information corresponding to the barring configurationinformation index mapped to the triggered access included in theimplicit barring list.

According to an embodiment of the disclosure, the method may furtherinclude determining to allow the access without performing the barringcheck, when there is no barring configuration information correspondingto the barring configuration information index mapped to the triggeredaccess.

According to an embodiment of the disclosure, an explicit barring listmay include at least one category-specific barring information, eachcategory-specific barring information including access categoryinformation and the barring configuration information index; and theperforming of the barring check may include in response to the barringlist type information indicating the explicit barring list, performingthe barring check based on barring configuration informationcorresponding to the barring configuration information index for theaccess category information corresponding to the triggered access.

According to an embodiment of the disclosure, a maximum number ofbarring configuration information able to be included in the barringconfiguration information list may be 8.

According to an embodiment of the disclosure, the barring configurationinformation may include barring information regarding a barring factor,a barring time, and an access identity.

According to an embodiment of the disclosure, the method may furtherinclude receiving, through an operations, administration, andmaintenance (OAM) message or a non-access stratum (NAS) message from thebase station, information regarding an operator-specific accesscategory, in which the performing of the barring check may includetriggering the access, mapping the triggered access to an accessidentity and an access category based on information about theinformation regarding the operator-specific access category, andperforming the barring check based on the access identity and the accesscategory.

According to an embodiment of the disclosure, the method may furtherinclude delaying the access when the access is not allowed according tothe barring check.

According to another aspect of the disclosure, a method, performed by abase station, of controlling an access in a mobile communication systemincludes determining whether to use an implicit barring list or anexplicit barring list, based on a preset criterion, generating theimplicit barring list including at least one barring configurationinformation index corresponding to at least one access category whendetermining to use the implicit barring list or generating the explicitbarring list including at least one category-specific barringinformation, each category-specific barring information including accesscategory information and the barring configuration information indexwhen determining to use the explicit barring list, and broadcasting,through system information, barring information comprising a barringconfiguration information list, the barring configuration informationlist comprising barring configuration information, the barringinformation further including at least one of the implicit barring listor the explicit barring list, in which the barring configurationinformation corresponds to one barring configuration information indexaccording to an order of being included in the barring configurationinformation list.

According to an embodiment of the disclosure, the method may furtherinclude generating the implicit barring list by mapping a barringconfiguration information index that is not mapped to the barringconfiguration information, to an access-allowed access category withoutperforming the barring check, when determining to use the implicitbarring list.

According to another aspect of the disclosure, a user equipment (UE)controlling an access in a mobile communication system includes acommunication unit and a controller configured to receive, throughsystem information from a base station, barring information including abarring configuration information list and a public land mobilenetwork(PLMN)-specific barring information list, the barringconfiguration information list including at least one barringconfiguration information and the PLMN-specific barring information listincluding at least one barring information per PLMN and to perform abarring check based on the received barring information when the accessis triggered, in which the barring configuration information correspondsto one barring configuration information index according to an order ofbeing included in the barring configuration information list.

According to an embodiment of the disclosure, the barring informationper PLMN may include a PLMN identification (ID) index and barring listtype information, and the controller may be configured in response tothe barring list type information indicating an implicit barring list,to perform the barring check based on barring configuration informationcorresponding to the barring configuration information index mapped tothe triggered access included in the implicit barring list.

According to an embodiment of the disclosure, the controller may befurther configured to determine to allow the access without performingthe barring check, when there is no barring configuration informationcorresponding to the barring configuration information index mapped tothe triggered access.

According to an embodiment of the disclosure, an explicit barring listmay include at least one category-specific barring information, eachcategory-specific barring information including access categoryinformation and the barring configuration information index, and thecontroller may be further configured to, in response to the barring listtype information indicating the explicit barring list, perform thebarring check based on barring configuration information correspondingto the barring configuration information index for the access categoryinformation corresponding to the triggered access.

According to an embodiment of the disclosure, a maximum number ofbarring configuration information able to be included in the barringconfiguration information list is 8.

According to an embodiment of the disclosure, the barring configurationinformation may include barring information regarding a barring factor,a barring time, and an access identity.

According to an embodiment of the disclosure, the controller may befurther configured to receive, through an operations, administration,and maintenance (OAM) message or a non-access stratum (NAS) message fromthe base station, information regarding an operator-specific accesscategory, trigger the access, map the triggered access to an accessidentity and an access category based on information about theinformation regarding the operator-specific access category, and performthe barring check based on the access identity and the access category.

According to an embodiment of the disclosure, the controller may befurther configured to delay the access when the access is not allowedaccording to the barring check.

According to another aspect of the disclosure, a base stationcontrolling an access in a mobile communication system includes acommunication unit and a controller configured to determine whether touse an implicit barring list or an explicit barring list, based on apreset criterion, to generate the implicit barring list including atleast one barring configuration information index corresponding to atleast one access category when determining to use the implicit barringlist or generating the explicit barring list including at least onecategory-specific barring information, each including access categoryinformation and the barring configuration information index whendetermining to use the explicit barring list, and to broadcast, throughsystem information, barring information comprising a barringconfiguration information list, the barring configuration informationlist comprising barring configuration information, the barringinformation further including at least one of the implicit barring listor the explicit barring list, in which the barring configurationinformation corresponds to one barring configuration information indexaccording to an order of being included in the barring configurationinformation list.

According to an embodiment of the disclosure, the controller may befurther configured to generate the implicit barring list by mapping abarring configuration information index that is not mapped to thebarring configuration information, to an access-allowed access categorywithout performing the barring check, when determining to use theimplicit barring list.

Before undertaking the DETAILED DESCRIPTION below, it may beadvantageous to set forth definitions of certain words and phrases usedthroughout this patent document: the terms “include” and “comprise,” aswell as derivatives thereof, mean inclusion without limitation; the term“or,” is inclusive, meaning and/or; the phrases “associated with” and“associated therewith,” as well as derivatives thereof, may mean toinclude, be included within, interconnect with, contain, be containedwithin, connect to or with, couple to or with, be communicable with,cooperate with, interleave, juxtapose, be proximate to, be bound to orwith, have, have a property of, or the like; and the term “controller”means any device, system or part thereof that controls at least oneoperation, such a device may be implemented in hardware, firmware orsoftware, or some combination of at least two of the same. It should benoted that the functionality associated with any particular controllermay be centralized or distributed, whether locally or remotely.

Moreover, various functions described below can be implemented orsupported by one or more computer programs, each of which is formed fromcomputer readable program code and embodied in a computer readablemedium. The terms “application” and “program” refer to one or morecomputer programs, software components, sets of instructions,procedures, functions, objects, classes, instances, related data, or aportion thereof adapted for implementation in a suitable computerreadable program code. The phrase “computer readable program code”includes any type of computer code, including source code, object code,and executable code. The phrase “computer readable medium” includes anytype of medium capable of being accessed by a computer, such as readonly memory (ROM), random access memory (RAM), a hard disk drive, acompact disc (CD), a digital video disc (DVD), or any other type ofmemory. A “non-transitory” computer readable medium excludes wired,wireless, optical, or other communication links that transporttransitory electrical or other signals. A non-transitory computerreadable medium includes media where data can be permanently stored andmedia where data can be stored and later overwritten, such as arewritable optical disc or an erasable memory device.

Definitions for certain words and phrases are provided throughout thispatent document, those of ordinary skill in the art should understandthat in many, if not most instances, such definitions apply to prior, aswell as future uses of such defined words and phrases.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects, features, and advantages of certainembodiments of the disclosure will be more apparent from the followingdescription taken in conjunction with the accompanying drawings, inwhich:

FIG. 1 illustrates a structure of an LTE system;

FIG. 2 illustrates a radio protocol architecture in an LTE system;

FIG. 3 illustrates a structure of a next-generation mobile communicationsystem to which an embodiment of the disclosure is applied;

FIG. 4 illustrates a radio protocol architecture of a next-generationmobile communication system to which an embodiment of the disclosure isapplied;

FIG. 5 illustrates a connection relationship among an LTE base station(evolved node B, eNB), a new radio (NR) base station (next generationnode B, gNB), an evolved packet core (EPC, LTE core network), and a 5Gcore network (CN, NR core network), supported by each of an LTE systemand a next-generation mobile communication system to which an embodimentof the disclosure is applied;

FIG. 6 illustrates a view for describing a structure of a network uniqueidentifier of each of an LTE system and a next-generation mobilecommunication system to which an embodiment of the disclosure isapplied;

FIG. 7 illustrates a ladder diagram describing operations in which userequipment (UE) attempting to initially access a network is assigned aunique identifier from a network and configures a connection with anetwork, according to an embodiment of the disclosure;

FIG. 8 illustrates a ladder diagram describing a method, performed by aUE assigned a first unique identifier from an LTE system, of configuringa connection to a network, according to an embodiment of the disclosure;

FIG. 9 illustrates a ladder diagram describing a method, performed by aUE assigned a second unique identifier from an NR system, of configuringa connection to a network, according to an embodiment of the disclosure;

FIG. 10 illustrates a flowchart of a method, performed by a UE havingreceived an RRCSetup message, of including 5G-S-TMSI informationprovided from an upper layer in an RRCSetupComplete message according toexistence or absence of the 5G-S-TMSI information, according to anembodiment of the disclosure;

FIG. 11 illustrates a block diagram of a structure of a UE according toan embodiment of the disclosure;

FIG. 12 illustrates a block diagram of a structure of a BS according toan embodiment of the disclosure;

FIG. 13 illustrates a structure of a next-generation mobilecommunication system to which another embodiment of the disclosure isapplied;

FIG. 14 illustrates a diagram for describing a process of performingaccess control with respect to a connected-mode or inactive-mode UEaccording to an embodiment of the disclosure;

FIG. 15 illustrates a diagram for describing a process of performingaccess control with respect to a connected-mode or inactive-mode UE inanother aspect, according to an embodiment of the disclosure;

FIG. 16 illustrates a diagram for describing a method of configuringaccess control information according to an embodiment of the disclosure;

FIG. 17 illustrates a flowchart of operations of an eNB according to anembodiment of the disclosure;

FIG. 18 illustrates a flowchart of operations of a UE according to anembodiment of the disclosure;

FIG. 19 illustrates a block diagram of a structure of a UE according toan embodiment of the disclosure; and

FIG. 20 illustrates a block diagram of a structure of an eNB accordingto an embodiment of the disclosure.

DETAILED DESCRIPTION

FIGS. 1 through 20, discussed below, and the various embodiments used todescribe the principles of the present disclosure in this patentdocument are by way of illustration only and should not be construed inany way to limit the scope of the disclosure. Those skilled in the artwill understand that the principles of the present disclosure may beimplemented in any suitably arranged system or device.

Hereinafter, various embodiments of the disclosure will be disclosedwith reference to the accompanying drawings.

When embodiments of the disclosure are described, technical matters thatare well known in a technical field of the disclosure and are notdirectly related to the disclosure will not be described. By omittingany unnecessary description, the subject matter of the disclosure willbe more clearly described without being obscured.

For the same reasons, some elements will be exaggerated, omitted, orsimplified in the attached drawings. The size of each element does notentirely reflect the actual size of the element. In each drawing, anidentical or corresponding element will be referred to as an identicalreference numeral.

Advantages and features of the disclosure and a method for achievingthem will be apparent with reference to embodiments of the disclosuredescribed below together with the attached drawings. However, thedisclosure is not limited to the disclosed embodiments of thedisclosure, but may be implemented in various ways, and the embodimentsof the disclosure are provided to complete the disclosure and to allowthose of ordinary skill in the art to understand the scope of thedisclosure. The disclosure is defined by the category of the claims.Throughout the specification, an identical reference numeral willindicate an identical element.

Meanwhile, it is known to those of ordinary skill in the art that blocksof a flowchart and a combination of flowcharts may be represented andexecuted by computer program instructions. These computer programinstructions may also be stored in a general-purpose computer, aspecial-purpose computer, or a processor of other programmable dataprocessing devices, such that the instructions implemented by thecomputer or the processor of the programmable data processing deviceproduce a means for performing functions specified in the flowchartand/or block diagram block or blocks. These computer programinstructions may also be stored in a computer usable orcomputer-readable memory that may direct a computer or otherprogrammable data processing apparatus to function in a particularmanner, such that the instructions stored in the computer usable orcomputer-readable memory produce an article of manufacture includinginstructions that implement the function specified in the flowchartand/or block diagram block or blocks. The computer program instructionsmay also be loaded onto a computer or other programmable data processingapparatus to cause a series of operational steps to be performed on thecomputer or other programmable apparatus to produce a computerimplemented process, such that the instructions that execute thecomputer or other programmable apparatus may provide steps forimplementing the functions specified in the flowchart and/or blockdiagram block or blocks.

In addition, each block represents a module, segment, or portion ofcode, which includes one or more executable instructions forimplementing the specified logical function(s). It should also be notedthat in other implementations, the function(s) noted in the blocks mayoccur out of the order indicated. For example, two blocks shown insuccession may, in fact, be executed substantially concurrently or theblocks may sometimes be executed in the reverse order, depending on thefunctionality involved.

In the current embodiment of the disclosure, the term ‘˜unit’, as usedherein, denotes a software or hardware component, such as a FieldProgrammable Gate Array (FPGA) or Application Specific IntegratedCircuit (ASIC), which performs certain tasks. However, the meaning of‘˜unit’ is not limited to software or hardware. ‘˜unit’ mayadvantageously be configured to reside on the addressable storage mediumand configured to reproduce one or more processors. Thus, a unit mayinclude, by way of example, components, such as software components,object-oriented software components, class components and taskcomponents, processes, functions, attributes, procedures, subroutines,segments of program code, drivers, firmware, microcode, circuitry, data,databases, data structures, tables, arrays, and variables. Thefunctionality provided for in the components and ‘˜unit(s)’ may becombined into fewer components and ‘˜unit(s)’ or further separated intoadditional components and ‘˜unit(s)’. In addition, components and‘˜unit(s)’ may be implemented to execute one or more CPUs in a device ora secure multimedia card. In the embodiments of the disclosure, ‘˜unit’may include one or more processors.

Throughout the disclosure, the expression “at least one of a, b or c”indicates only a, only b, only c, both a and b, both a and c, both b andc, all of a, b, and c, or variations thereof

As used in the following description, a term for identifying an accessnode, terms referring to network entities, terms referring to messages,a term referring to an interface between network objects, and termsreferring to various identification information are illustrated forconvenience of explanation. Therefore, the disclosure is not limited bythe following terms, and other terms referring to objects havingequivalent technical meanings may be used.

In the disclosure, for convenience of description, the disclosure usesterms and names defined in standards regarding 5^(th)-Generation (5G),New Radio (NR), or Long Term Evolution (LTE) systems. However, thedisclosure is not limited by such terms and names, and may be equallyapplied to systems complying with other standards.

While a description will be focused on a communication standardspecified by the 3GPP, when embodiments of the disclosure are describedin detail, a main subject matter to be claimed in the specification isalso applicable to other communication systems and services having asimilar technical background without significantly departing from arange disclosed herein, as will be obvious to those of ordinary skill inthe art.

In a next-generation mobile communication system (5G or NR system), morevarious types of wireless communication devices as well as mobilephones, Node B (NB)-Internet of Things (IoT) devices, and sensors mayconfigure a connection to a network. Therefore, to manage numerouswireless communication devices, a next-generation mobile communicationsystem needs to introduce a new identifier having a larger space andassign different identifiers to manage wireless communication devices.However, when new identifiers having larger spaces are introduced,wireless communication devices assigned with the new identifiers need toprovide a method of delivering the new identifiers to a network based ona circumstance.

The following description will be made of a method and apparatus for, bya UE, processing a new identifier provided from a network, in a networkaccess stage, a state transition stage, a network reconfiguration stage,etc. Throughout the specification, a layer may also be referred to as anentity.

FIG. 1 illustrates a structure of an LTE system.

Referring to FIG. 1, a radio access network of the LTE system mayinclude a plurality of evolved nodes B (eNB, Node B, or base station) 1a-05, 1 a-10, 1 a-15, and 1 a-20, a mobility management entity (MME) 1a-25, and a serving gateway (S-GW) 1 a-30. A user equipment (UE orterminal) 1 a-35 may access an external network through the eNBs 1 a-05,1 a-10, 1 a-15, and 1 a-20 and the S-GW 1 a-30.

The eNBs (Nodes B or base stations) 1 a-05, 1 a-10, 1 a-15, and 1 a-20may provide, as access nodes of a cellular network, radio accesses toUEs accessing the network. That is, the eNBs 1 a-05, 1 a-10, 1 a-15, and1 a-20 collect state information, such as UEs' buffer statuses,available transmission power states, and channel states, performscheduling, and support connections between the UEs and a core network(CN), so as to provide a traffic service of users.

The eNBs 1 a-05, 1 a-10, 1 a-15, and 1 a-20 correspond to existing NodesB in a Universal Mobile Telecommunication System (UMTS) system. The eNBs1 a-05 may be connected with the UE 1 a-35 through a radio channel andplay more complicated roles than the existing Node B. In the LTE system,every user traffic as well as a real-time service such as voice overInternet protocol (VoIP) is provided through a shared channel, requiringa device for collecting state information of UEs, such as a bufferstate, an available transmit power state, a channel state, etc., andperforming scheduling based on the state information, and examples ofsuch a device may be the eNBs 1 a-05, 1 a-10, 1 a-15, and 1 a-20. OneeNB may generally control multiple cells. The LTE system may use, forexample, orthogonal frequency division multiplexing (OFDM) as a wirelessconnection scheme. Also, adaptive modulation & coding (AMC) may be usedin which a modulation scheme and a channel coding rate are determineddepending on a channel state of a UE.

The MME 1 a-25 is in charge of various control functions as well as amobility management function for the UE, and is connected with theplurality of ENBs. The S-GW 1 a-30 may be a device that provides a databearer. The MME 1 a-25 and the S-GW 1 a-30 may perform authentication,bearer management, etc., with respect to a UE accessing the network, andprocess a packet having arrived from the eNBs 1 a-05, 1 a-10, 1 a-15,and 1 a-20 or packets to be delivered to the eNBs 1 a-05, 1 a-10, 1a-15, and 1 a-20.

FIG. 2 illustrates a radio protocol architecture in an LTE system.

Referring to FIG. 2, a radio protocol of the LTE system may includepacket data convergence protocols (PDCPs) 1 b-05 and 1 b-40, radio linkcontrols (RLCs) 1 b-10 and 1 b-35, and medium access controls (MACs) 1b-15 and 1 b-30, respectively, at a UE and an eNB. The PDCPs 1 b-05 and1 b-40 are responsible for IP header compression/decompression or thelike. Main functions of the PDCPs are summarized as follows:

-   -   Header compression and decompression: (ROHC only)    -   Transfer of user data    -   In-sequence delivery of upper-layer PDUs at PDCP        re-establishment procedure for RLC AM    -   For split bearers in DC (only support for RLC AM): PDCP PDU        routing for transmission and PDCP PDU reordering for reception    -   Duplicate detection of lower-layer SDUs at PDCP re-establishment        procedure for RLCAM    -   Retransmission of PDCP SDUs at handover and, for split bearers        in DC, of PDCP PDUs at PDCP data-recovery procedure, for RLC AM    -   Ciphering and deciphering    -   Timer-based SDU discard in uplink

The RLCs 1 b-10 and 1 b-35 may reconstruct a PDCP packet data unit (PDU)into a proper size and perform an automatic request for repetition (ARQ)operation. Main functions of the RLCs are summarized as follows:

-   -   Transfer of upper layer PDUs    -   Error Correction through ARQ (only for AM data transfer)    -   Concatenation, segmentation and reassembly of RLC SDUs (only for        UM and AM data transfer)    -   Re-segmentation of RLC data PDUs (only for AM data transfer)    -   Reordering of RLC data PDUs (only for UM and AM data transfer)    -   Duplicate detection (only for UM and AM data transfer)    -   Protocol error detection (only for AM data transfer)    -   RLC SDU discard (only for UM and AM data transfer)    -   RLC re-establishment

The MACs 1 b-15 and 1 b-30 may be connected to a plurality of RLC-layerdevices configured in one UE, multiplex RLC PDUs into a MAC PDU, anddemultiplex an MAC PDU into RLC PDUs. Main functions of the MACs aresummarized as follows:

-   -   Mapping between logical channels and transport channels    -   Multiplexing/demultiplexing of MAC SDUs belonging to one or        different logical channels into/from transport blocks (TB)        delivered to/from the physical layer on transport channels    -   Scheduling information reporting    -   Error correction through HARQ    -   Priority handling between logical channels of one UE    -   Priority handling between UEs by means of dynamic scheduling    -   MBMS service identification    -   Transport format selection    -   Padding

Physical (PHY) layers 1 b-20 and 1 b-25 may perform channel coding andmodulation of upper-layer data and convert the data into OFDM symbols totransmit the OFDM symbols through a radio channel, or demodulate OFDMsymbols received through a radio channel and perform channel decoding ofthe OFDM symbols to deliver the OFDM symbols to an upper layer.

Although not shown in FIG. 2, a radio resource control (RRC) layer mayexist on the PDCP layers of the UE and the eNB, respectively, and theRRC layer may exchange a configuration control message related to accessor measurement for radio resource control.

FIG. 3 illustrates a structure of a next-generation mobile communicationsystem to which an embodiment of the disclosure is applied.

Referring to FIG. 3, a radio access network of the next-generationmobile communication system (5G or NR system) may include a new radionode B (NR NB, NR gNB, or NR eNB) 1 c-10 and a new radio core network(NR CN or a next generation core network (NG CN) 1 c-05. A new radiouser equipment (NR UE or UE) 1 c-15 may access an external networkthrough the NR gNB 1 c-10 and the NR CN 1 c-05.

In FIG. 3, the NR gNB 1 c-10 may correspond to an evolved Node B (eNB)of an LTE system. The NR gNB 1 c-10 may be connected to the NR UE 1 c-15over a radio channel and may provide a more advanced service than thatof the existing Node B. In the next-generation mobile communicationsystem, all user traffic is served through a shared channel, requiring adevice that collects state information, such as UEs' buffer status,available transmission power state, and channel state, and performsscheduling, in which the NR gNB 1 c-10 may be responsible for thesefunctions. One NR gNB 1 c-10 may generally control a plurality of cells,and include a central unit (CU) managing control and signaling and adistributed unit (DU) in charge of signal transmission/reception. Inorder to realize ultra-high-speed data transmission compared to an LTEsystem, the next-generation mobile communication system (5G or NRsystem) may have a maximum bandwidth greater than the existing maximumbandwidth and may employ a beamforming technique in addition to OFDM asa radio access technology. Also, adaptive modulation & coding (AMC) maybe used in which a modulation scheme and a channel coding rate aredetermined based on a channel state of a UE. The NR CN 1 c-05 mayperform functions such as mobility support, bearer setup, QoS setup,etc. The NR CN 1 c-05 may be a device that performs not only a mobilitymanagement function for a UE but also various control functions and maybe connected to a plurality of base stations. The next-generation mobilecommunication system (5G or NR system) may also interwork with theexisting LTE system, in which the NR CN 1 c-105 may be connected to anMME 1 c-25 through a network interface. The MME 1 c-25 may be connectedto the eNB 1 c-30, which is an existing eNB.

FIG. 4 illustrates a radio protocol architecture of a next-generationmobile communication system to which an embodiment of the disclosure isapplied.

Referring to FIG. 4, a radio protocol of the next-generation mobilecommunication system (5G or NR system) may include NR SDAPs 1 d-01 andld-45, NR PDCPs 1 d-05 and 1 d-40, NR RLCs 1 d-10 and 1 d-35, and NRMACs 1 d-15 and 1 d-30, respectively at a UE and an NR gNB.

Main functions of the NR SDAPs 1 d-01 and 1 d-45 may include some of thefollowing functions:

-   -   Transfer of user plane data    -   Mapping between a QoS flow and a DRB for both DL and UL    -   Marking QoS flow identification (ID) in both DL and UL packets    -   Mapping of reflective QoS flow to DRB for the UL SDAP PDUs

For an SDAP layer device, a UE may be set whether to use a header of anSDAP layer device or a function of the SDAP layer device for each PDCPlayer device or each bearer or logical channel through an RRC message.When an SDAP header is set, it may be indicated using a network attachedstorage (NAS) QoS reflective configuration 1-bit indicator (NASreflective QoS) and an AS QoS reflective configuration 1-bit indicator(AS reflective QoS) that the UE may update or reconfigure a QoS flow ofan uplink and a downlink and mapping information regarding a databearer. The SDAP header may include QoS flow ID information indicating aQoS. The QoS information may be used as data processing priorityinformation, scheduling information, etc., for supporting a smoothservice.

Main functions of the NR PDCPs 1 d-05 and 1 d-40 may include some of thefollowing functions:

Header compression and decompression: (ROHC only)

Transfer of user data

In-sequence delivery of upper layer PDUs

Out-of-sequence delivery of upper layer PDUs

PDCP PDU reordering for reception

Duplicate detection of lower layer SDUs

Retransmission of PDCP SDUs

Ciphering and deciphering

Timer-based SDU discard in uplink)

Herein, the reordering function of the NR PDCP devices refers to afunction of rearranging PDCP PDUs received in a lower layer in orderbased on a PDCP sequence number (SN), and may include a function oftransmitting data to an upper layer in the order of rearrangement or afunction of immediately transmitting the data regardless of order, andmay also include a function of recording lost PDCP PDUs throughreordering, a function of reporting the state of lost PDCP PDUs to atransmitter, and a function of requesting retransmission of lost PDCPPDUs.

Main functions of the NR RLCs 1 d-10 and 1 d-35 may include some of thefollowing functions:

Transfer of upper layer PDUs

In-sequence delivery of upper layer PDUs

Out-of-sequence delivery of upper layer PDUs

Error correction through ARQ

Concatenation, segmentation and reassembly of RLC SDUs

Re-segmentation of RLC data PDUs

Reordering of RLC data PDUs

Duplicate detection

Protocol error detection

RLC SDU discard

RLC re-establishment

Herein, the in-sequence delivery function of the NR RLC devices refersto a function of delivering RLC SDUs received from a lower layer to anupper layer in order. More specifically, the in-sequence deliveryfunction of the NR RLC devices may include a function of re-assemblingand delivering a plurality of RLC SDUs when one original RLCSDU isdivided into the plurality of RLC SDUs to be received, a function ofrearranging received RLC PDUs based on the RLC SN or the PDCP SN, afunction of recording lost RLC PDUs through reordering, a function ofreporting the state of lost RLC PDUs to a transmitter, a function ofrequesting retransmission of lost RLC PDUs, a function of deliveringonly RLC SDUs before a lost RLC SDU to an upper layer in order in caseof the presence of the lost RLC SDU, a function of delivering all RLCSDUs, received before a timer starts, to an upper layer in order whenthe timer has expired despite the presence of a lost RLC SDU, and afunction of delivering all RLC SDUs received so far to an upper layer inorder when the timer expires despite the presence of a lost RLC SDU.

The NR RLC devices may process RLC PDUs in order of reception (the orderof arrival regardless of the order of SNs) and deliver the RLC PDUs tothe PDCP devices in an out-of-sequence manner, and for a segment, the NRRLC devices may receive segments that are stored in a buffer or are tobe received later, may reconstruct the segment into one whole RLC PDU,may process the RLC PDU, and may deliver the RLC PDU to the PDCPdevices. The NR RLC layers may not include a concatenation function, andthe concatenation function may be performed in the NR MAC layers or maybe replaced with a multiplexing function of the NR MAC layers.

Herein, the out-of-sequence delivery function of the NR RLC devicesrefers to a function of delivering RLC SDUs received from a lower layerdirectly to an upper layer regardless of order, and may include afunction of re-assembling and delivering a plurality of RLC SDUs whenone original RLC SDU is divided into the plurality of RLC SDUs to bereceived, and a function of recording lost RLC PDUs by storing andreordering the RLC SNs or PDCP SNs of received RLC PDUs.

The NR MACs 1 d-15 and 1 d-30 may be connected to a plurality of NRRLC-layer devices configured in one UE, and main functions of the NRMACs may include some of the following functions:

Mapping between logical channels and transport channels

Multiplexing/demultiplexing of MAC SDUs

Scheduling information reporting

Error correction through HARQ

Priority handling between logical channels of one UE

Priority handling between UEs by means of dynamic scheduling

MBMS service identification

Transport format selection

Padding

NR PHYs 1 d-20 and 1 d-25 may perform channel coding and modulation ofupper-layer data and convert the data into OFDM symbols to transmit theOFDM symbols through a radio channel, or demodulate OFDM symbolsreceived through a radio channel and perform channel decoding of theOFDM symbols to deliver the OFDM symbols to an upper layer.

FIG. 5 illustrates a connection relationship among an LTE base station(eNB), an NR base station (gNB), an EPC (LTE core network), and a 5G CN(NR core network), supported by each of an LTE system and anext-generation mobile communication system to which an embodiment ofthe disclosure is applied.

An EPC may be a network including an MME, and a 5G CN may be a networkincluding an access management function (AMF).

Referring to FIG. 5, there may be various connection relationships suchas a case where an LTE eNB is connected to an EPC as indicated by 1e-01, a case where an LTE eNB are connected to both an EPC and a 5G CNas indicated by 1 e-02, a case where an LTE eNB is connected to a 5G CNas indicated by 1 e-03, and a case where an NR gNB is connected to a 5GCN as indicated by 1 e-04.

In the disclosure, a description will be made of a network connectionmethod and RRC message information for a UE, in which various connectionrelationships may be supported including connection relationships amongan LTE eNB, an NR gNB, an EPC (LTE core network), and a 5G CN (NR corenetwork) described in FIG. 5.

FIG. 6 illustrates a view for describing a structure of a network uniqueidentifier of each of an LTE system and a next-generation mobilecommunication system to which an embodiment of the disclosure isapplied.

In a next-generation mobile communication system, to distinguish andmanage more wireless communication devices and support networkconnection in an LTE system, a UE unique identifier in a network may beintroduced as an identifier having a space that is equal to or largerthan that of a unique identifier in the LTE system. In particular, in anetwork, unique identifiers, a 5G-globally unique temporary UE identity(GUTI) and a 5G-SAE temporary mobile subscriber identity (5G-S-TMSI) maybe set different from a GUTI and an S-TMSI of an LTE system.

First, FIG. 6 illustrates a structure of a GUTI [80 bits] in an LTEsystem. Referring to FIG. 6, in an LTE system, a structure of a GUTI [80bits] may include a mobile country code (MCC) [12 bits] 1 f-05, a mobilenetwork code (MNC) [12 bits] 1 f-10, MME identifiers [24 bits] 1 f-15and 1 f-20, and an MME TMSI [32 bits] 1 f-25. That is, in the LTEsystem, a GUTI may be expressed as a sum of a network identifier of anMME existing per network operator in one country and a UE identifieruniquely assigned in the MME, i.e., an M-TMSI. Herein, an MME identifiermay include an MME group ID [16 bits] 1 f-15 and an MME code [8 bits] 1f-20, and a globally unique MME identifier (GUMMEI) [48 bits] mayinclude an MCC, an MNC, and an MME identifier. An EPC of the LTE systemmay assign a GUTI distinguishable by the LTE system to an initiallyaccessing UE. An identifier distinguishable by an LTE eNB accessstratum, i.e., an S-TMSI [40 bits] may be configured as a part of a GUTIfor use. Herein, the S-TMSI may include an MME code 1 f-20 and an M-TMSI1 f-25.

In a 5G or NR system, a length of a unique identifier owned by a UE isglobally maintained, while a length of an identifier owned by the UE inthe network, i.e., distinguishable in a 5G or NR eNBs access stratum, a5G-S-TMSI is increased, thus increasing the number of UEs accessible inthe network.

FIG. 6 illustrates a structure of a 5G-GUTI [80 bits] in a 5G or NRsystem. Referring to FIG. 6, in a 5G or NR system, a structure of a5G-GUTI [80 bits] may include an MCC [12 bits] 1 f-30, an MNC [12 bits]1 f-35, AMF identifiers [24 bits] 1 f-40, 1 f-45, and 1 f-50, and a5G-TMSI [32 bits] 1 f-55. That is, in the 5G or NR system, a 5G-GUTI maybe expressed as a sum of a network identifier of an AMF existing pernetwork operator in one country and a UE identifier uniquely assigned inthe AMF, i.e., an 5G-TMSI. Herein, an AMF identifier may include an AMFset ID [10 bits] 1 f-40, an AMF region ID [8 bits] 1 f-45, and an AMFpointer [6 bits] 1 f-50, and a globally unique AMF identifier (GUAMI)[48 bits] may include an MCC, an MNC, and an AMF identifier. A 5G or NRCN of the 5G or NR system may assign a GUTI distinguishable by the NRsystem to an initially accessing UE. An identifier distinguishable by anNR eNB access stratum, i.e., an 5G-S-TMSI [48 bits] may be configured asa part of a GUTI for use. Herein, the 5G-S-TMSI may include an AMFregion ID 1 f-45, an AMF pointer 1 f-50, and a 5G-TMSI 1 f-55.

As shown in FIG. 6, a 5G or NR system may configure a 5G-S-TMSI of 48bits, which is increased by 8 bits from in the LTE system, and assignthe 48-bit 5G-S-TMSI to the UE, in which case a determination is made asto whether a size of a message 3 (msg 3, Message 3) carrying the5G-S-TMSI is sufficient. Examples of the message 3 may include an RRCsetup request, an RRC resume request, an RRC reestablishment request,etc. In the LTE system, the message 3 of 56 bits is used, and in the 5Gor NR system, a minimum uplink grant size is 56 bits without beingchanged. The message 3 is a request message attempting connection to anetwork, necessitating good link performance in a cell coverage. Asmaller size of a packet transmitted by the UE expands a UE coverage,such that assignment of an uplink grant of 56 bits or more may causedegraded cell access coverage performance. As a result, in the 5G or NRsystem, to distinguish an uplink grant of 56 bits and an uplink grant of56 bits or more (e.g., 72 bit) for common control channel (CCCH)transmission from each other, a separate logical channel identifier(LCID) is further assigned to a MAC header. However, when the 56-bituplink grant is assigned, the 5G-S-TMSI increased by 8 bits from theS-TMSI of the LTE may not be entirely carried in the message 3, suchthat a part of the 5G-S-TMSI may be transmitted in the message 3 and theother part may be transmitted in a message 5 (msg 5, message 5). Forexample, 39 bits of the 5G-S-TMSI assigned from the network may bedelivered through the message 3 and the other 9 bits may be deliveredthrough the message 5. The message 3 may be an RRC setup requestmessage, and the message 5 may be an RRC setup complete message.

In the 56-bit uplink grant, a MAC PDU including a MAC PDU header [8bits] and a CCCH [48 bits] may be delivered. Herein, the CCCH messagemay be the message 3, and for example, when the RRC setup requestmessage is used, 2 bits for identifying the RRC setup request messageamong types of uplink CCCH messages are used, and 1 bit in a CHOICEstructure for future extension is used.

UL-CCCH-Message ::= SEQUENCE { message UL-CCCH-MessageType }UL-CCCH-MessageType ::= CHOICE { c1 CHOICE { rrcSetupRequestRRCSetupRequest, rrcResumeRequest RRCResumeRequest,rrcReestablishmentRequest RRCReestablishmentRequest,rrcSystemInfoRequest RRCSystemInfoRequest }, messageClassExtensionSEQUENCE { } }

In addition, 2 bits of a CHOICE structure for distinguishing three typesof UE identities of the RRC setup request message and least significantbit (LSB) information of the 5G-S-TMSI of a maximum of 39 bits (39 bitsfrom the right of total bits) are used. Moreover, 4 bits for identifyinga maximum of 16 establishmentcause are used.

RRCSetupRequest ::= SEQUENCE { rrcSetupRequest RRCSetupRequest-IEs }RRCSetupRequest-IEs ::= SEQUENCE { ue-Identity InitialUE-Identity,establishmentCause EstablishmentCause } InitialUE-Identity ::= CHOICE {ng-5g-s-tmsi-part1 BIT STRING (SIZE (39)), randomValue BIT STRING (SIZE(39)), spare BIT STRING (SIZE (1)) } -- FFS Which additional causevalues are supported: delayTolerantAccess, MO videop, MO SMS, etc.EstablishmentCause ::= ENUMERATED { emergency, highPriorityAccess,mt-Access, mo-Signalling, mo-Data, mo-VoiceCall,spare1, spare2,spare3,spare4, spare5, spare6, spare7, spare8, spare9, spare10}

That is, the 56-bit uplink grant includes the following information:

MAC header [8 bits]

[3 bits] for identifying an uplink CCCH message

RRCSetupReqeust [45 bits] {(ue-Identity: [2 bits]+[39 bits])+(causevalue: [4 bits])}

The message 5 may include most significant bit (MSB) information (9 bitsfrom the left of the total bits) of the 9-bit 5G-S-TMSI. For example,the RRC connection complete message may be configured as below.

RRCSetupComplete ::= SEQUENCE { rrc-TransactionIdentifierRRC-TransactionIdentifier, criticalExtensions CHOICE { c1 CHOICE{rrcSetupComplete RRCSetupComplete-IEs, spare3 NULL, spare2 NULL, spare1NULL }, criticalExtensionsFuture SEQUENCE { } } } RRCSetupComplete-IEs::= SEQUENCE { selectedPLBN-Identity INTEGER (1..maxPLMN), registeredAMFRegisteredAMF OPTIONAL, guami-Type ENUMERATED (native, mapped) OPTIDNAL,s-nssai-list SEQUENCE (SIZE (1..maxNrofS-NSSAI)) OF S-NSSAI OPTIONAL,dedicatedInfoNAS DedicatedInfoNAS, ng-5G-S-TMSI-Value CHOICE {ng-5g-s-tmsi NG-5G-S-TMSI, ng-5g-s-tmsi-part2 BIT STRING (SIZE (9)) }OPTIONAL,

Hereinbelow, a description will be made of a method of attempting toconnect to a network by carrying a 5G-S-TMSI that is a UE's identifierin a distributed manner through the message 3 and the message 5.

In an embodiment of the disclosure, when the UE attempts to connect tothe network, a 39-bit part of the 5G-S-TMSI may be transmitted throughthe RRC setup request message. When there is 5G-S-TMSI informationassigned from the network, 39-bit LSBs of the 5G-S-TMSI information maybe included, but when there is no 5G-S-TMSI information assigned fromthe network, a 39-bit random value may be produced and included in themessage 3 to attempt to access the network. Thereafter, the UE mayreceive an RRC setup message that is a message 4 (msg 4, Message 4) fromthe network, and the UE having received the message may perform aprocedure for a connection to an eNB by using the entire 5G-S-TMSI or9-bit MSBs of the 5G-S-TMSI based on a state of the UE.

However, in the 5G or NR system, in addition to an operation based onthe above-described RRC setup procedure, the UE having sent an RRCresume request and an RRC reestablishment request may receive an RRCsetup (Message 4) from an eNB in response to a request for the message3. The operation corresponding to this case will be described in detail.That is, a description will be made of how to deliver the 5G-S-TMSI byusing the message 5 in a particular case.

FIG. 7 illustrates a ladder diagram describing operations in which a UEattempting to initially access a network is assigned a unique identifierfrom a network and configures a connection with a network, according toan embodiment of the disclosure.

A UE initially attempting to access a network may mean a UE which hasnot ever performed registration in an LTE system and a 5G or NR systembefore. That is, the initially attempting UE may mean a UE that has notbeen assigned with a first unique identifier (GUTI) or a second uniqueidentifier (5G-GUTI) from the LTE system or the 5G or NR system.

Referring to FIG. 7, a UE in an RRC idle mode, when initially accessingthe network, may start a search for a cell, perform cellselection/reselection to find a suitable cell, and camp on the foundcell. The UE may be synchronized with the camping-on cell and perform arandom access procedure. In the random access procedure, when the UEtransmits a message 3 (e.g., 56 bits (8 bits of a MAC header and 48 bitsof a CCCH SDU) through a CCCH, the UE may transmit random values havinga specific length (e.g., 40 bits or 39 bits) through the message 3 (CCCHSDU) in operation 1 g-05.

The eNB or gNB having received the message 3 (CCCH SDU) may identicallycopy the first 6 bytes of the received message 3 (CCCH SDU) forcontention resolution, include the copied first 6 bytes in MAC controlinformation (MAC control element, contention resolution MAC CE), andtransmit the same to the UE through a message 4 in operation 1 g-10. TheUE having received the message 4 may identify contention resolution andtransmit a message 5 to the eNB or gNB in operation 1 g-15. Herein, theUE may carry a UE-unique identifier (e.g., an IMSI) to the networkthrough an NAS container (dedicatedInfoNAS) of the message 5, such thatthe network may identify the UE-unique identifier and register the UE inthe network.

Thereafter, the eNB or gNB may receive the message 5 and identifynetwork information in the message 5, thus routing the messages from theUE to a CN (MME or AMF). The eNB or gNB may also transmit NAS containerinformation included in the message 5 to the CN (the EPC or the 5G or NRCN) through an NAS message (e.g., an INITIAL CONTEXT REQUEST or SERVICEREQUEST) in operation 1 g-20. The CN may identify the unique identifierof the UE, register the UE in the CN, determine to assign a uniqueidentifier (GUTI/5G-TMSI or S-TMSI/5G-S-TMSI) for identifying the UE ina network system (the LTE system or the 5G or NR system), and transmitthe assigned unique identifier to the eNB or gNB through an NAS message(e.g., INITIAL CONTEXT SETUP) to deliver the assigned unique identifierto the UE in operation 1 g-25. The eNB or gNB may deliver the message tothe UE in operation 1 g-30. When the UE is registered in the LTE systemthrough the received message, the UE may identify a first uniqueidentifier (GUTI), and when the UE is registered in the 5G or NR system,the UE may identify a second unique identifier (5G-GUTI) and store thesame in an NAS layer device in operation 1 g-30. When the eNB or gNBtransmits an RRC Connection Reconfiguration message to configure RRCconnection, the UE may receive the RRC Connection Reconfigurationmessage in operation 1 g-35 and complete configuration by receiving eachbearer configuration information. Thereafter, the UE may transmit an RRCConnection Reconfiguration Complete message to the eNB or gNB tocomplete connection configuration in operation 1 g-40. The eNB or gNBmay complete connection configuration with the UE and transmit aresponse indicating completion of initial connection and contextconfiguration to the CN in operation 1 g-45. The UE may completeconnection configuration with the network and thus be able to exchangedata with the network in operation 1 g-50.

FIG. 8 illustrates a ladder diagram describing a method, performed by aUE assigned a first unique identifier from an LTE system, of configuringa connection to a network, according to an embodiment of the disclosure.

The UE assigned with the first unique identifier (GUTI) from the LTEsystem may mean a UE that has registered in the LTE system and thusstored the first unique identifier (GUTI) therein.

Referring to FIG. 8, the UE in the RRC idle mode may re-attempt toconnect to a network when the UE receives a paging message or needs toupdate a tracking area or to transmit data in an uplink. The UE maystart a search for a cell, perform cell selection/reselection to find asuitable cell, and camp on the found cell. The UE may be synchronizedwith the camping-on cell and perform a random access procedure. In therandom access procedure, when the UE transmits a message 3 (e.g., 56bits (8 bits of an MAC header and 48 bits of a CCCH SDU) through a CCCH,to perform contention resolution among UEs, the eNB may define a part ofthe first unique identifier (GUTI) previously assigned from the LTEsystem, instead of the random values, as a first identifier (e.g., theS-TMSI) for identifying the UE among eNBs, and transmit the firstidentifier through the message 3. That is, LSBs (e.g., 40 LSBs) of thefirst unique identifier (e.g., the GUTI) stored in the UE may betransmitted as the first identifier (e.g., the S-TMSI) through themessage 3 (CCCH SDU) in operation 1 h-05.

In the message 3, an indicator may be defined and included, whichindicates whether a value corresponding to the identifier included inthe message 3 is the 40-bit random value described in FIG. 7 or thefirst identifier (S-TMSI) to allow the eNB to distinguish the randomvalue and the first identifier from each other. For example, a 1-bitindicator may be used to indicate the random value or the firstidentifier. The eNB or gNB having received the message 3 may identicallycopy the first 6 bytes of the received message 3 (CCCH SDU) forcontention resolution, include the copied first 6 bytes (48 bits) in MACcontrol information (MAC control element, contention resolution MAC CE),and transmit the same to the UE through a message 4 in operation 1 h-10.The UE having received the message 4 may identify contention resolutionand transmit the message 5 to the eNB or gNB in operation 1 h-15.Herein, the UE may carry the first unique identifier (e.g., the GUTI)assigned from the LTE system and stored, to the network through an NAScontainer (dedicatedInfoNAS) of the message 5, such that the network mayidentify the first unique identifier and the UE.

Thereafter, the eNB may identify the first identifier (S-TMSI) andreceive the message 5. The eNB may identify network information in themessage 5, thus routing the messages from the UE to a CN (MME). The eNBmay also transmit NAS container information included in the message 5 tothe CN (the EPC or the 5G or NR CN) through an NAS message (e.g., anINITIAL CONTEXT REQUEST or SERVICE REQUEST) in operation 1 h-20. The eNBmay identify the first identifier, and may transmit a SERVICE REQUESTmessage to the CN when the eNB determines that the UE is a registered UEand the UE re-connects and requests a service. The CN may identify theUE's unique identifier, that is, the network system (LTE system or 5G orNR system) identifies the UE and a context, and transmit the firstunique identifier (e.g., the IMSI) to the eNB through the NAS (e.g.,INITIAL CONTEXT SETUP) message to allow UE's connection in operation 1h-25. The eNB may transmit the received NAS message to the UE. When theeNB transmits an RRC Connection Reconfiguration message to configure RRCconnection in operation 1 h-35, the UE may receive the RRC ConnectionReconfiguration message in operation and complete configuration byreceiving each bearer configuration information in operation 1 h-35.Thereafter, the UE may transmit an RRC Connection ReconfigurationComplete message to the eNB or gNB to complete connection configurationin operation 1 h-40. The eNB may complete connection configuration withthe UE and transmit a response indicating completion of initialconnection and context configuration to the CN in operation 1 h-45. TheUE may complete connection configuration with the network and thus beable to exchange data with the network in operation 1 h-50.

FIG. 9 illustrates a ladder diagram describing a method, performed by aUE assigned a second unique identifier from an NR system, of configuringa connection to a network, according to an embodiment of the disclosure.

The UE assigned with the second unique identifier (5G-GUTI) from the 5Gor NR system may mean a UE that has registered in the 5G or NR systemand thus stored the second unique identifier (5G-GUTI) therein.

To identify and manage more wireless communication devices and supportconnection to a network, a next-generation mobile communication systemmay introduce the second unique identifier (5G-GUTI) as an identifierhaving a larger space than the first unique identifier (GUTI), and asecond identifier (e.g., a 48-bit 5G-S-TMSI) as an identifier having alarger space than the first identifier (e.g., a 40-bit S-TMSI).

In an embodiment of the disclosure, the message 3 may be transmittedthrough the CCCH and is a key message used for the UE to configureconnection to the network, such that a coverage may be a key issue. Thecoverage may be expanded when as small data as possible is transmitted,and thus in an embodiment of the disclosure, the size of the message 3may be limited to the size of a minimum transport block to maximize thecoverage. For example, the message 3 may have a size of 56 bits.However, the second unique identifier (5G-GUTI) having a larger or equalspace may be introduced, such that the second identifier having thelarger or equal space may be used when the UE access the network. Thatis, the size of the minimum transport block may be insufficient toinclude the new second identifier. Thus, when the UE attempts to accessthe network by using the second identifier having the larger space, theUE may use the indicator of the message 3 to indicate that a part of thesecond identifier is to be transmitted through the message 3 and theother part of the second identifier is to be transmitted through themessage 5, such that the eNB may normally receive the second identifierhaving the larger space.

Referring to FIG. 9, the UE in the RRC idle mode may re-attempt toconnect to a network when the UE receives a paging message or needs toupdate a tracking area or to transmit data in an uplink. The UE maystart a search for a cell, perform cell selection/reselection to find asuitable cell, and camp on the found cell. The UE may be synchronizedwith the camping-on cell and perform a random access procedure. In therandom access procedure, when the UE transmits a message 3 (e.g., 56bits (8 bits of an MAC header and 48 bits of a CCCH SDU) through a CCCH,to perform contention resolution among UEs, the eNB may define a part ofthe second unique identifier previously assigned from the 5G or NRsystem, instead of the random values, as a second identifier (e.g., the5G-S-TMSI) for identifying the UE among eNBs, and transmit the firstidentifier through the message 3. However, the size of the secondidentifier (5G-S-TMSI) may be large, e.g., 48 bits, and thus the UE maytransmit the second identifier to the eNB in a distributed mannerthrough the message 3 and the message 5. That is, LSBs (e.g., 39 LSBs)of the second unique identifier (e.g., the 5G-S-TMSI) stored in the UEmay be transmitted through the message 3 (CCCH SDU) in operation 1 i-05.

In the message 3, an indicator may be defined and included, whichindicates whether a value corresponding to the identifier included inthe message 3 is the random value or the second identifier to allow theeNB to identify a part of the second identifier. For suchidentification, a 2-bit identifier may be used also for future extraexpansion. The eNB or gNB having received the message 3 may identicallycopy the first 6 bytes of the received message 3 (CCCH SDU) forcontention resolution, include the copied first 6 bytes (48 bits) in MACcontrol information (MAC control element, contention resolution MAC CE),and transmit the same to the UE through a message 4 in operation 1 i-10.The UE having received the message 4 may identify contention resolutionand transmit the message 5 to the eNB or gNB in operation 1 i-15.Herein, the UE may transmit through the message 5, a part (e.g., 9 MSBs)of the second identifier other than the part of the second identifiertransmitted through the message 3. The UE may carry the second uniqueidentifier (e.g., the 5G-GUTI) assigned from the 5G or NR system andstored, to the network through an NAS container (dedicatedInfoNAS) ofthe message 5, such that the network may identify the second uniqueidentifier and the UE.

Thereafter, the eNB may identify the second identifier (5G-S-TMSI)included in the message 3 and the message 5 in the distributed manner,and identify network information in the message 5, thus routing themessages from the UE to a CN (AMF). The eNB may also transmit NAScontainer information included in the message 5 to the CN (the EPC orthe 5G or NR CN) through an NAS message (e.g., an INITIAL CONTEXTREQUEST or SERVICE REQUEST) in operation 1 i-20. The eNB may identifythe second identifier, and may transmit a SERVICE REQUEST message to theCN when the eNB determines that the UE is a registered UE and the UEre-connects and requests a service. The CN may identify the UE's uniqueidentifier, that is, the network system (LTE system or 5G or NR system)identifies the UE and a context, and transmit the second uniqueidentifier (e.g., the IMSI) to the eNB through the NAS (e.g., INITIALCONTEXT SETUP) message to allow UE's connection in operation 1 i-25. TheeNB may transmit the received NAS message to the UE. When the eNBtransmits an RRC Connection Reconfiguration message to configure RRCconnection in operation 1 i-35, the UE may receive the RRC ConnectionReconfiguration message in operation and complete configuration byreceiving each bearer configuration information in operation 1 i-35.Thereafter, the UE may transmit an RRC Connection ReconfigurationComplete message to the eNB or gNB to complete connection configurationin operation 1 i-40. The eNB may complete connection configuration withthe UE and transmit a response indicating completion of initialconnection and context configuration to the CN in operation 1 i-45. TheUE may complete connection configuration with the network and thus beable to exchange data with the network in operation 1 i-50.

While a description has been made with reference to FIGS. 8 and 9regarding a general operation after the UE is provided with the secondidentifier (5G-S-TMSI) from upper layers (the NSA and the CN), transmitsthe RRC Setup Request message (message 3), and receives the RRC Setupmessage through the message 4 in the 5G or NR system, the UE may alsoreceive the RRC Setup message (message 4) as a fallback case in the 5Gor NR system. The fallback case corresponds to a case where when the UEtransmits an RRC Reestablishment Request message or an RRC ResumeRequest message, the eNB delivers an RRC Setup message to instruct theUE to re-establish RRC connection. Also in the fallback case, the UE maydeliver the RRC Setup Complete message through the message 5 because theUE has received the RRC Setup message through the message 4. When the UEreceives the RRC Setup message in response to the RRC ReestablishmentRequest message or the RRC Resume Request message, the UE may not beprovided with the second identifier (5G-S-TMSI) from the upper layer inan initialization process of a procedure (RRC Reestablishment or RRCResume) for a request, and the RRC Setup Complete message of the message5 may include the entire second identifier (5G-S-TMSI) rather than 9MSBs of the second identifier (5G-S-TMSI). This case corresponds to acase where the message 5 includes the effective second identifier(5G-S-TMSI) provided from the upper layer by the UE prior to an RRCReestablishment or RRC Resume procedure, and 39 LSBs of the secondidentifier (5G-S-TMSI) are not delivered in a distributed manner in themessage 3 (RRC Reestablishment Request or RRC Resume Request message) ofthe procedure, such that the message 5 (RRC Setup Complete message)includes the entire second identifier (5G-S-TMSI). Table 1 shows a casewhere the second identifier (5G-S-TMSI) is included in the message 3 andthe message 5.

TABLE 1 Whether 5G-S-TMSI 5G-S-TMSI value is provided by upper includedin layer in initialization RRCSetupComplete Case of procedure messageCase 1. Provided Including 9 MSBs When RRC Setup message of 5G-S-TMSI istriggered by (set ng-5G-S-TMSI- RRCSetupRequest message Value tong-5G-s- including 39 LSBs of 5G-S- tmsi-part2) TMSI as UE-identity Case2. Not Provided Not including When RRC Setup message 5G-S-TMSI istriggered by information RRCSetupRequest message including 39-bit randomvalue as UE-identity Case 3. Not Provided (or Not Including total 48When RRC Setup message Sure) bits of 5G-S-TMSI is triggered by (setng-5G-S-TMSI- RRCReestablish- Value to NG-5G-S- mentRequest messageTMSI) Case 4. Not Provided (or Not Including total 48 When RRC Setupmessage Sure) bits of 5G-S-TMSI is triggered by (set ng-5G-S-TMSI-RRCResumeRequest Value to NG-5G-S- message TMSI)

Hereinbelow, a description will be made of a method, performed by a UEhaving received an RRCSetup message, of including 5G-S-TMSI informationprovided from an upper layer in the message 5 (RRCSetupComplete message)according to existence or absence of the 5G-S-TMSI information,including the above-described fallback case.

FIG. 10 illustrates a flowchart of a method, performed by a UE havingreceived an RRCSetup message, of including 5G-S-TMSI informationprovided from an upper layer in an RRCSetupComplete message according toexistence or absence of the 5G-S-TMSI information, according to anembodiment of the disclosure.

Referring to FIG. 10, the UE in the RRC idle mode may re-attempt toaccess a network when the UE receives a paging message or needs toupdate a tracking area or to transmit data in an uplink. The UE maystart a search for a cell, perform cell selection/reselection to find asuitable cell, camp on the found cell, and receive system informationfrom the eNB. The UE may be synchronized with the camping-on cell andperform a random access procedure in operation 1 j-10. In the randomaccess procedure, the UE may transmit the message 3 through the CCCH.Through transmission of the message 3, the following RRC message may beconfigured and transmitted based on a current state of the UE and apurpose of a request with respect to a network.

-   -   RRCSetupRequest: When the UE initially accesses the network or        newly requests connection due to disconnection in spite of        connection to the eNB (message configuration may differ        according to a case where the 5G-S-TMSI is provided from an        upper layer and a case where the 5G-S-TMSI is not provided from        an upper layer)    -   RRCResumRequest: When the UE having connected to the network        transits to an inactive state for a particular reason, but        requests connection to the network for reasons such as        generation of data, RAN area update, etc.    -   RRCReestablishmentRequest: When the UE connects to the network        and link connection is released for a particular reason (e.g., a        radio link failure), but the UE requests an attempt to the eNB

The above-described UE operation indicates a UE operation prior to ageneral RRCSetupRequest procedure, but operation 1 j-15 includes theentire procedure for transmitting RRCResumeRequest and RRCResumeRequest.That is, an operation at 1 j-15 may differ with a status of the UE. Inoperation 1 j-20, the UE may receive the RRCSetup message from the eNBthrough the message 4 and establishes SRB1. As discussed above, the RRCSetup message may be configured by the eNB regardless of a type of amessage requested by the UE, and in view of the UE, an operation mayvary with a message request, in response to which the RRCSetup messageis received. In operation 1 j-25, the UE may determine a method forincluding the 5G-S-TMSI in the RRCSetupComplete message according to themessage 3 (RRCSetupRequest, RRCResumeRequest, orRRCReestablishmentRequest), in response to which the RRCSetup messagereceived in operation 1 j-20 is triggered.

When the UE corresponds to Case 1 of Table 1 (the RRC Setup message istriggered by the RRCSetupRequest message including the 39 LSBs of the5G-S-TMSI as the UE-identity) in operation 1 j-25, the UE is providedwith the 5G-S-TMSI from an upper layer before transmission of themessage 3 (RRCSetupRequest), such that the 39 LSBs of the 5G-S-TMSI areincluded in the message 3, and thus the UE may generate theRRCSetupComplete message including the other 9 MSBs of the 5G-S-TMSI inoperation 1 j-30.

When the UE corresponds to Case 2 of Table 1 (the RRC Setup message istriggered by the RRCSetupRequest message including a random value of 39bits as the UE-identity) in operation 1 j-25, the UE is not providedwith the 5G-S-TMSI from an upper layer before transmission of themessage 3 (RRCSetupRequest), such that the random value instead of the5G-S-TMSI is included in the message 3, and thus the UE may generate theRRCSetupComplete message without including information about the5G-S-TMSI in operation 1 j-35. That is, none of the entire informationand partial information of the 5G-S-TMSI is included in the message 5.

When the UE corresponds to Case 3 of Table 1 (the RRC Setup message istriggered by the RRCReestablishmentRequest message) in operation 1 j-25,the UE is not provided with the 5G-S-TMSI from an upper layer at thetime of transmission of the message 3 (RRCReestablishmentRequest) and avalid 5G-S-TMSI received from the upper layer at the time of previousconnection with the network is stored, such that information related tothe 5G-S-TMSI is not included in the message 3(RRCReestablishmentRequest), and thus the UE may generate theRRCSetupComplete message including the entire 48-bit 5G-S-TMSI inoperation 1 j-40.

When the UE corresponds to Case 4 of Table 1 (the RRC Setup message istriggered by the RRCResumeRequest message) in operation 1 j-25, the UEis not provided with the 5G-S from an upper layer at the time oftransmission of the message 4 (RRCResumeRequest) and a valid 5G-S-TMSIreceived from the upper layer at the time of previous connection withthe network is stored, such that information related to the 5G-S-TMSI isnot included in the message 3 (RRCResumeRequest), and thus the UE maygenerate the RRCSetupComplete message including the entire 48-bit5G-S-TMSI in operation 1 j-45.

After a UE operation per case is performed, the UE may set the message 5(RRCSetupComplete) by including the other contents than the 5G-S-TMSI inoperation 1 j-50. In operation 1 j-55, the UE may transmit theRRCSetupComplete message generated in operation 1 j-50 to the eNB.

UE operations described with reference to FIG. 10 may be expressed asbelow in the standards.

Camping on a cell

Receiving MIB and SIB 1

Triggering random access procedure

Transmitting CCCH SDU in the Msg 3

Receiving RRCSetupRequest and establish SRB1

Determine the type ng-5g-s-tmsi to be included in RRCSetupCompletemessage and set the contents as below:

1> set the content of RRCSetupComplete message as follows:

-   -   2> if upper layers provide an 5G-S-TMSI and RRCSetup is received        in response to an RRCSetupRequest:        -   3> Include ng-5G-s-tmsi-part2 in RRCSetupComplete message        -   3> set the ng-5g-s-tmsi-bits to ng-5G-s-tmsi-part2;    -   2> else if the RRCSetup is received in response to an        RRCReestablishmentRequest or RRCResumeRequest: (or higher layer        have provided valid ng-5G-s-tmsi and UE have stored it)        -   3> Include ng-5G-s-tmsi in RRCSetupComplete message        -   3> set the ng-5g-s-tmsi-bits set to ng-5g-s-tmsi;    -   2> else if the RRCSetup is received in response to RRCSetup and        upper layer does not provide an 5G-S-TMSI:        -   3> do not include ng-5G-s-tmsi-part2 nor ng-5g-s-tmsi in the            RRCSetupComplete message

Setting the other contents of RRCSetupComplete

Transmitting RRCSetupComplete message

FIG. 11 illustrates a block diagram of a structure of a UE according toan embodiment of the disclosure.

Referring to FIG. 11, the UE may include a radio frequency (RF)processor 1 k-10, a baseband processor 1 k-20, a storage unit 1 k-30,and a controller 1 k-40.

The RF processor 1 k-10 may perform a function for transmitting andreceiving a signal through a wireless channel, such as band translation,amplification, and so forth. That is, the RF processor 1 k-10up-converts a baseband signal provided from the baseband processor 1k-20 into an RF band signal, transmits the RF band signal through anantenna, and down-converts an RF band signal received through theantenna into a baseband signal. For example, the RF processor 1 k-10 mayinclude a transmission filter, a reception filter, an amplifier, amixer, an oscillator, a digital-to-analog converter (DAC), ananalog-to-digital converter (ADC), and so forth. Although one antenna isillustrated in FIG. 11, the UE may also include multiple antennas. TheRF processor 1 k-10 may include multiple RF chains. The RF processor 1k-10 may perform beamforming. For the beamforming, the RF processor 1k-10 may adjust phases and magnitudes of signals transmitted andreceived through multiple antennas or antenna elements. The RF processor1 k-10 may also perform MIMO and may receive several layers whenperforming MIMO operations.

The baseband processor 1 k-20 performs conversion between a basebandsignal and a bitstream according to physical layer standards of asystem. For example, in data transmission, the baseband processor 1 k-20may generate complex symbols by encoding and modulating a transmissionbitstream. In data reception, the baseband processor 1 k-20 may recovera received bitstream by demodulating and decoding the baseband signalprovided from the RF processor 1 k-10. For example, when orthogonalfrequency division multiplexing (OFDM) is used, in data transmission,the baseband processor 1 k-20 may generate complex symbols by encodingand modulating a transmission bitstream, map the complex symbols tosubcarriers, and construct OFDM symbols through inverse fast Fouriertransform (IFFT) and cyclic prefix (CP) insertion. Also, in datareception, the baseband processor 1 k-20 divides the baseband signalprovided from the RF processor 1 k-10 in the unit of an OFDM symbol,recovers the signals mapped to the subcarriers through FFT, and recoversthe received bitstream through demodulation and decoding.

The baseband processor 1 k-20 and the RF processor 1 k-10 transmit andreceive a signal as described above. Thus, the baseband processor 1 k-20and the RF processor 1 k-10 may be indicated by a transmitter, areceiver, a transceiver, or a communicator. Moreover, at least one ofthe baseband processor 1 k-20 or the RF processor 1 k-10 may includemultiple communication modules for supporting multiple different radioaccess technologies. In addition, at least one of the baseband processor1 k-20 or the RF processor 1 k-10 may include multiple communicationmodules for processing signals in different frequency bands. Forexample, the different radio access technologies may include a wirelessLAN (e.g., IEEE 802.11), a cellular network (e.g., LTE), and the like.In addition, the different frequency bands may include a super highfrequency (SHF, e.g., 2.5 GHz, 5 GHz) band, and a millimeter wave(mm-wave, e.g., 60 GHz) band.

The storage unit 1 k-30 stores data such as a basic program foroperations of the UE, an application program, configuration information,and so forth. The storage unit 1 k-30 provides the stored data at therequest of the controller 1 k-40.

The controller 1 k-40 controls overall operations of the UE. Forexample, the controller 1 k-40 may transmit and receive a signal throughthe baseband processor 1 k-20 and the RF processor 1 k-10. Thecontroller 1 k-40 records and reads data from and in the storage unit 1k-30. To this end, the controller 1 k-40 may include at least oneprocessor. According to an embodiment of the disclosure, the controller1 k-40 includes a multi-connection processor 1 k-42 configured toperform processing to operate in a multi-connection mode. For example,the controller 1 k-40 may control the UE of FIG. 1k -42 to perform aprocedure of operations of the UE For example, the controller 1 k-40 mayinclude a communication processor (CP) for performing control forcommunication and an application processor (AP) for controlling a higherlayer such as an application program.

FIG. 12 illustrates a block diagram of a structure of an eNB accordingto an embodiment of the disclosure.

As shown in FIG. 12, the eNB may include an RF processor 1 l-10, abaseband processor 1 l-20, a backhaul communicator 1 l-30, a storageunit 1 l-40, and a controller 1 l-50.

The RF processor 1 l-10 performs a function for transmitting andreceiving a signal through a wireless channel, such as band translation,amplification, and so forth. That is, the RF processor 1 l-10up-converts a baseband signal provided from the baseband processor 1l-20 into an RF band signal, transmits the RF band signal through anantenna, and down-converts an RF band signal received through theantenna into a baseband signal. For example, the RF processor 1 l-10 mayinclude a transmission filter, a reception filter, an amplifier, amixer, an oscillator, a DAC, an ADC, and so forth. Although one antennais illustrated in FIG. 12, the UE may also include multiple antennas.The RF processor 1 l-10 may include multiple RF chains. The RF processor1 l-10 may perform beamforming. For the beamforming, the RF processor 1l-10 may adjust phases and magnitudes of signals transmitted andreceived through multiple antennas or antenna elements. The RF processor1 l-10 may perform downward MIMO operations by transmitting one or morelayers.

The baseband processor 1 l-20 performs conversion between a basebandsignal and a bitstream according to physical layer standards. Forexample, in data transmission, the baseband processor 1 l-20 maygenerate complex symbols by encoding and modulating a transmissionbitstream. In data reception, the baseband processor 1 l-20 may recovera received bitstream by demodulating and decoding the baseband signalprovided from the RF processor 1 l-10. For example, when OFDM is used,in data transmission, the baseband processor 1 l-20 may generate complexsymbols by encoding and modulating a transmission bitstream, map thecomplex symbols to subcarriers, and construct OFDM symbols through IFFTand CP insertion. Also, in data reception, the baseband processor 1 l-20divides the baseband signal provided from the RF processor 1 l-10 in theunit of an OFDM symbol, recovers the signals mapped to the subcarriersthrough FFT, and recovers the received bitstream through demodulationand decoding. The baseband processor 1 l-20 and the RF processor 1 l-10transmit and receive a signal as described above. Thus, the basebandprocessor 1 l-20 and the RF processor 1 l-10 may be indicated by atransmitter, a receiver, a transceiver, a communicator, or a wirelesscommunicator.

The backhaul communicator 1 l-30 provides an interface for performingcommunication with other nodes in a network. That is, the backhaulcommunicator 1 l-30 converts a bitstream transmitted to another node,e.g., an auxiliary eNB, a core network, etc., into a physical signal,and converts a physical signal received from the another node into abitstream.

The storage unit 1 l-40 stores data such as a basic program foroperations of the main eNB, an application program, configurationinformation, and so forth. In particular, the storage unit 1 l-40 storesinformation about a bearer allocated to the connected UE, and ameasurement result reported from the connected UE. The storage unit 1l-40 stores information that is a criterion for determining whether toprovide multiple connections to the UE or to stop providing the multipleconnections to the UE. The storage unit 1 l-40 provides the stored dataat the request of the controller 1 l-50.

The controller 1 l-50 controls overall operations of the main eNB. Forexample, the controller 1 l-50 may transmit and receive a signal throughthe baseband processor 1 l-20 and the RF processor 1 l-10 or through thebackhaul communicator 1 l-30. The controller 1 l-50 records and readsdata from and in the storage unit 1 l-40. To this end, the controller 1l-50 may include at least one processor. According to an embodiment ofthe disclosure, the controller 1 l-50 includes a multi-connectionprocessor 1 l-52 configured to perform processing to operate in amulti-connection mode.

According to an embodiment of the disclosure, a method for networkidentifier management and access by an UE may be clarified, such that anaccess using a new identifier may be supported in a 5G or NR system.

Hereinbelow, a method and apparatus for providing access controlinformation in a next-generation mobile communication system (5G or NRsystem) will be described.

FIG. 13 illustrates a structure of a next-generation mobilecommunication system.

Referring to FIG. 13, a radio access network of the next-generationmobile communication system (NR system) may include a new radio node B(gNB) 2 a-10 and an AMF (NR CN) 2 a-05. An NR UE or UE 2 a-15 may accessthe external network through the gNB 2 a-10 and the AMF 2 a-05.

In FIG. 13, the gNB 2 a-10 may correspond to an eNB 2 a-30 of anexisting LTE system. The gNB 2 a-10 may be connected to the NR UE 2 a-15over a radio channel and may provide a more advanced service than thatof the existing Node B, as indicated by 2 a-20. In the next-generationmobile communication system, all user traffic is served through a sharedchannel, requiring a device that collects state information, such asUEs' buffer status, available transmission power state, and channelstate, and performs scheduling, in which the gNB 2 a-10 may beresponsible for these functions. One gNB 2 a-10 may generally control aplurality of cells. In order to realize ultra-high-speed datatransmission compared to an LTE system, the next-generation mobilecommunication system (5G or NR system) may have a maximum bandwidthgreater than the existing maximum bandwidth and may employ a beamformingtechnique in addition to OFDM as a radio access technology. Also,adaptive modulation & coding (AMC) is used in which a modulation schemeand a channel coding rate are determined depending on a channel state ofa UE.

The AMF 2 a-05 may perform functions such as mobility support, bearersetup, QoS setup, etc. The AMF 2 a-05 is in charge of various controlfunctions as well as a mobility management function for the UE, and isconnected with the plurality of ENBs. The next-generation mobilecommunication system may also interwork with the existing LTE system, inwhich the AMF 2 a-105 may be connected to an MME 2 a-25 through anetwork interface. The MME 2 a-25 may be connected to the eNB 2 a-30,which is an existing eNB. The UE supporting LTE-NR dual connectivity maytransmit and receive data, while maintaining connection with the eNB 2a-30 as well as the gNB 2 a-10, as indicated by 2 a-35.

FIG. 14 illustrates a diagram for describing a process of performingaccess control with respect to a connected-mode or inactive-mode UEaccording to an embodiment of the disclosure.

According to an embodiment of the disclosure, access controlconfiguration information based on an access identity and an accesscategory may be effectively provided. The access identity is indicationinformation defined in the 3GPP, i.e., specified in the standarddocument. The access identity is used to indicate a particular access asin Table 2. The access identity mainly indicates accesses classified asAccess Classes 11 through 15, a multimedia priority service (MPS), and amission critical service (MCS). Access Classes 11 through 15 indicateaccesses dedicated for operators, participants, or for public purposes.

TABLE 2 Access Identity number UE configuration 0 UE is not configuredwith any parameters from this table  1 (NOTE 1) UE is configured forMultimedia Priority Service (MPS).  2 (NOTE 2) UE is configured forMission Critical Service (MCS). 3-10 Reserved for future use 11 (NOTE 3)Access Class 11 is configured in the UE. 12 (NOTE 3) Access Class 12 isconfigured in the UE. 13 (NOTE 3) Access Class 13 is configured in theUE. 14 (NOTE 3) Access Class 14 is configured in the UE. 15 (NOTE 3)Access Class 15 is configured in the UE. NOTE 1: Access Identity 1 isused to provide overrides according to the subscription information inUEs configured for MPS. The subscription information defines whether anoveride applies to UEs within one of the following categories: a) UEsthat are configured for MPS; b) UEs that are configured for MPS and arein the PLMN listed as most preferred PLMN of the country where the UE isroaming in the operator-defined PLMN selector list or in their HPLMN ofin a PLMN that is equivalent to their HPLMN; c) UEs that are configuredfor MPS and are in their HPLMN or in a PLMN that is equivalent to it.NOTE 2: Access Identity 2 is used to provide overrides according to thesubscription information in UEs configured for MCS. The subscriptioninformation defines whether an overide applies to UEs within one of thefollowing categories: a) UEs that are configured for MCS; b) UEs thatare configured for MCS and are in the PLMN listed as most preferred PLMNof the country where the UE is roaming in the operator-defined PLMNselector list or in their HPLMN or in a PLMN that is equivalent to theirHPLMN; c) UEs that are configured for MCS and are in their HPLMN or in aPLMN that is equivalent to it. NOTE 3: Access Identities 11 and 15 arevalid in Home PLMN only if the EHPLMN list is not present or in anyEHPLMN. Access Identities 12, 13 and 14 are valid in Home PLMN andvisited PLMNs of home country only. For this purpose the home country isdefined as the country of the MCC part of the IMSI.

The access category may be classified into two types. The first type maybe a standardized access category. The standardized access category maybe a category defined in a RAN level, that is, specified in the standarddocument. Thus, the same standardized access category may be applied todifferent operators. In an embodiment of the disclosure, a categorycorresponding to Emergency may be included in the standardized accesscategory. Every access may correspond to at least one of standardizedaccess categories. The other type may be an operator-specific(non-standardized) access category. The operator-specific(non-standardized) access category may be defined outside the 3GPP, andmay not be specified in the standard document. Thus, oneoperator-specific access category means differently from operator tooperator. This nature is the same as that of a category in an existingapplication specific congestion control for data communication (ACDC).An access triggered in the UE NAS may not be mapped to theoperator-specific access category. A major difference from the existingACDC is that a corresponding category may correspond to not only anapplication, but also other elements than the application, i.e., aservice type, a call type, a UE type, a user group, a signaling type, aslice type, or a combination of the elements. That is, whether toapprove an access may be controlled for accesses included in otherelements. The access category may be used to indicate a particularaccess as in Table 3. Access categories 0 to 7 may be used to indicatethe standardized access category, and access categories 32 to 63 may beused to indicate the operator-specific access category.

TABLE 3 Access Category Type of access number Conditions related to UEattempt 0 All MO Signalling resulting from paging    1 (NOTE 1) UE isconfigured for delay All except for tolerant service and subject toEmergency access control for Access Category 1, which is judged based anrelation of UE's HPLMN and the selected PLMN. 2 All Emergency 3 Allexcept for the conditions MO signalling in Access Category 1. resultingfrom other than paging 4 All except for the conditions MMTEL voice inAccess Category 1. 5 All except for the conditions MMTEL video in AccessCategory 1. 6 All except for the conditions SMS in Access Category 1. 7All except for the conditions MO data that do in Access Category 1. notbelong to any other Access Categories 8-31 Reserved standardized AccessCategories 32-63 (NOTE 2) All Based on operator classification NOTE 1:The barring parameter for Access Category 1 is accompanied withinformation that define whether Access Category applies to UEs withinone of the following categories: a) UEs that are configured for delaytolerant service; b) UEs that are configured for delay tolerant serviceand are neither in their HPLMN nor in a PLMN that is equivalent to it;c) UEs that are configured for delay tolerant service and are neither inthe PLMN listed as most preferred PLMN of the country where the UE isroaming in the operator-defined PLMN selector list on the SIM/USIM, norin their HPLMN nor in a PLMN that is equivalent to their HPLMN. NOTE 2:When there are an Access Category based on operator classification and astandardized Access Category to both of which an access attempt can becategorized, and the standardized Access Category is neither 0 nor 2,the UE applies the Access Category based on operator classification.When there are an Access Category based on operator classification and astandardized Access Category to both of which an access attempt can becategorized, and the standardized Access Category is 0 or 2, the UEapplies the standardized Access Category.

An operator server 2 b-25 may provide information about theoperator-specific access category, a management object (MO) to the UENAS through NAS signaling or application-level data transmission. Theinformation about the operator-specific access category may includeinformation about which element, such as an element, eachoperator-specific category corresponds to. For example, it may beindicated in information regarding the operator-specific access categorythat the access category 32 corresponds to an access corresponding to aparticular application (e.g., a Facebook application). A gNB 2 b-20 mayprovide a category list including barring configuration information andbarring configuration information corresponding to each category to UEs.A UE 2 b-05 may include logical blocks of an NAS 2 b-10 and an AS 2b-15.

The UE NAS may map a triggered access to one or more access identitiesand one or more access categories according to a specific rule. Such amapping operation is performed in all RRC states, i.e., a connected mode(RRC_CONNECTED), an idle mode (RRC_IDLE), and an inactive mode(RRCC_INACTIVE). Characteristics of each RRC state are as follows:

-   RRC_IDLE:    -   A UE specific DRX may be configured by upper layers;    -   UE controlled mobility based on network configuration;    -   The UE:    -   Monitors a Paging channel;    -   Performs neighbouring cell measurements and cell (re-)selection;    -   Acquires system information.-   RRC_INACTIVE:    -   A UE specific DRX may be configured by upper layers or by RRC        layer;    -   UE controlled mobility based on network configuration;    -   The UE stores the AS context;    -   The UE:    -   Monitors a Paging channel;    -   Performs neighbouring cell measurements and cell (re-)selection;    -   Performs RAN-based notification area updates when moving outside        the RAN-based notification area;    -   Acquires system information.-   RRC_CONNECTED:    -   The UE stores the AS context.    -   Transfer of unicast data to/from UE.    -   At lower layers, the UE may be configured with a UE specific        DRX.;    -   For UEs supporting CA, use of one or more SCells, aggregated        with the SpCell, for increased bandwidth;    -   For UEs supporting DC, use of one SCG, aggregated with the MCG,        for increased bandwidth;    -   Network controlled mobility, i.e. handover within NR and to/from        E-UTRAN.    -   The UE:    -   Monitors a Paging channel;    -   Monitors control channels associated with the shared data        channel to determine if data is scheduled for it;    -   Provides channel quality and feedback information;    -   Performs neighbouring cell measurements and measurement        reporting;    -   Acquires system information.

In another option, in access category mapping, when one access ismappable to one standardized access category, the access may further bemapped to one operator-specific access category. The UE NAS may deliveran access identity and an access category that are mapped together witha service request to the UE AS.

When the UE AS is provided with access identity or access categoryinformation together with a message received from the UE NAS in all RRCstates, the UE AS performs a barring check operation of determiningwhether a radio access caused by the message is allowed beforeperforming the radio access. When the radio access is allowed through abarring check operation, the UE AS requests RRC connection setup. Forexample, an NAS of the UE in the connected mode or the inactive mode maytransmit an access identity and an access category to the UE AS forreasons provided below as indicated by 2 b-30. In an embodiment of thedisclosure, the reasons will be collectively referred to as a ‘newsession request’.

new MINITEL voice or video session

sending of SMS (SMS over IP, or SMS over NAS)

new PDU session establishment

existing PDU session modification

service request to re-establish the user plane for an existing PDUsession

On the other hand, the NAS of the idle-mode UE may transmit an accessidentity and an access category when the NAS transmits a service requestmessage.

The UE AS may determine using the barring configuration informationwhether an access triggered by the UE NAS is allowed (barring check).

An operator may would like to allow a particular service type amongaccesses corresponding to at least one of Access Classes 11 through 15.Thus, in an embodiment of the disclosure, whether to allow accessesbelonging to Access Classes 11, 12, 13, 14, and 15 indicated by accessidentifies may be determined based on attributes distinguished by theaccess category. To this end, a method of configuring barringconfiguration information of an access identity or access category willbe described. In an embodiment of the disclosure, the barringconfiguration information of the access category may includeac-barringFactor and ac-barringTime like in barring configurationinformation of existing access class barring (ACB) or ACDC.

FIG. 15 illustrates a diagram for describing a process of performingaccess control with respect to a connected-mode or inactive-mode UE inanother aspect, according to an embodiment of the disclosure.

A UE 2 c-05 may include an NAS 2 c-10 and an AS 2 c-15. The NAS isresponsible for processes that are directly related to wirelessconnection, i.e., authentication, service request, and sessionmanagement, and the AS is responsible for processes related to wirelessconnection. The network may provide management object information to anNAS by using an operation, administration, and maintenance (OAM) (a datamessage in an application level) or NAS message in operation 2 c-25. Themanagement object information may indicate an element, for example, anapplication, etc., to which each operator-specific access categorycorresponds. The NAS may use the management object information todetermine an operator-specific category to which a triggered access ismapped. The triggered access may correspond to a new MMTEL service(voice call and video call), SMS transmission, new PDU sessionestablishment, existing PDU session change, etc. The NAS may mapattributes of the service with corresponding access identity and accesscategory when the service is triggered, in operation 2 c-30.

The service may not be mapped with any access identity, but may bemapped with one or more access identities. The service may be mappedwith one access category. When the service is mapped with one accesscategory, it is first determined whether the service is mapped with anoperator-specific access category provided by the management object.When the service is not mapped with any operator-specific accesscategory, the service may be mapped with corresponding one of thestandardized access categories. When the service is mapped with aplurality of access categories, one service may be mapped with oneoperator-specific access category and one standardized access category.However, when the service is not mapped with any operator-specificaccess category, the service may be mapped with a corresponding one ofthe standardized access categories.

In such a mapping rule, an emergency service may be an exception. TheNAS may transmit a new session request or a service request, togetherwith the mapped access identity and access category, to the AS inoperation 2 c-40. The NAS may transmit the new session request in theconnected mode or the inactive mode and the service request in the idlemode. The AS may receive barring configuration information from systeminformation broadcast by the network in operation 2 c-35. An example ofa structure of ASN.1 of barring configuration information is as below,and a detailed description thereof will be provided below.

UAC-BarringPerPLMN-List ::= SEQUENCE (SIZE (1.. maxPLMN)) OFUAC-BarringPerPLMN UAC-BarringPerPLMN ::= SEQUENCE { plmn-IdentityIndexINTEGER (1..maxPLMN), uac-ACBarringListType CHOICE{uac-ImplicitACBarringList SEQUENCE (SIZE(maxAccessCat-1)) OFUAC-BarringInfoSetIndex, uac-ExplicitACBarringList UAC-BarringPerCatList} } UAC-BarringPerCatList ::= SEQUENCE (SIZE (1..maxAccessCat-1)) OFUAC-BarringPerCat UAC-BarringperCat ::= SEQUENCE {  accessCategoryINTEGER (1..maxAccessCat-1),  uac-barringInfoSetIndexUAC-BarringInfoSetIndex } UAC-BarringInfoSetIndex ::= INTEGER(1..maxBarringInfoSet) UAC-BarringInfoSetList ::= SEQUENCE (SIZE(1..maxBarringInfoSet)) OF UAC-BarringInfoSet UAC-BarringInfoSet ::=SEQUENCE { uac-BarringFactor ENUMERATED { p00, p05, p10, p15, p20, p25,p30, p40, p50, p60, p70, p75, p80, p85, p90, p95}, uac-BarringTimeENUMERATED (s4, s8, s16, s32, s64, s128, s256, s512),uac-BarringForAccessIdentity BIT STRING (SIZE(7)) }

The AS may determine whether the service request is allowed, by usingthe mapped access identity and access category information mapped by theNAS and the corresponding barring configuration information receivedfrom the network in operation 2 c-45. In an embodiment of thedisclosure, an operation of determining whether the service request isallowed will be referred to as barring check. The UE may receive systeminformation including access control configuration information and storeconfiguration information. The barring configuration information may beprovided per public land mobile network (PLMN) and access category. ABarringPerCatList IE may be used to provide barring configurationinformation of access categories belonging to one PLMN. To this end, aPLMN id and barring configuration information of each access categorymay be included in an IE in the form of a list. In barring configurationinformation per access category, an access category id (or index)indicating a particular access category, a uac-BarringForAccessIdentityfield, a uac-BarringFactor field, and a uac-Barringtime field may beincluded. The above-described barring check operation is as below.First, each bit constituting uac-BarringForAccessIdentityList maycorrespond to one access identity, in which a bit value ‘0’ indicatesthat an access related to an access identity is allowed. For at leastone of the mapped access identities, when at least one of correspondingbits in uac-BarringForAccessIdentity is ‘0’, an access is allowed. Forat least one of the mapped access identities, when any one of thecorresponding bits in uac-BarringForAccessIdentity is not ‘0’, anadditional barring check may be performed by further using auac-BarringFactor field. uac-BarringFactor α may be in a range of 0≤α<1.The UE AS may derive a random value rand in a range of 0≤rand<1, anddetermine that the access is not prohibited when the random value isless than uac-BarringFactor, and determine that the access is prohibitedotherwise. When the UE AS determines that the access is prohibited, theUE AS may delay an access attempt during a time derived usingEquation 1. The UE AS may drive a timer having a specific time value. Inan embodiment of the disclosure, the timer may be referred to as abarring timer.

“Tbarring”=(0.7+0.6*rand)*uac-BarringTime  Equation 1

When the access is prohibited, the UE AS may notify so to the UE NAS.When the derived time has expired, the UE AS may notify to the UE NASthat an access is requested again (barring alleviation). From thatpoint, the UE NAS may request again an access from the UE AS.

According to a specific rule, when a service request is allowed, the ASmay transmit an RRC connection establishment request or RRC connectionresume request or data related to a new session to the network inoperation 2 c-50.

FIG. 16 illustrates a diagram for describing a method of configuringaccess control information according to an embodiment of the disclosure.

In an embodiment of the disclosure, access control information mayinclude UAC-BarringPerPLMN-List 2 d-05 and UAC-BarringInfoSetList 2d-60. Barring configuration information including ac-BarringFactor,uac-BarringTime, and uac-BarringForAccessIdentity may be provided foreach access category. The barring configuration information per accesscategory may differ with PLMN. UAC-BarringPerPLMN-List may includebarring configuration information of access categories per PLMN. Interms of signaling overhead, it may be desirable to provide barringconfiguration information for access categories requiring barring check.For more efficient signaling, when a list of a limited number of barringconfiguration information may be provided and barring configurationinformation applied for each access category is indexed from the list,then the signaling overhead may be minimized. The list may beUAC-BarringInfoSetList, and may include UAC-BarringInfoSet 2 d-65 havingincluded thereto barring configuration information that is set to aparticular value. In an order of the included UAC-BarringInfoSet, oneindex value uac-barringInfoSetIndex may correspond to theUAC-BarringInfoSet. The maximum number of UAC-BarringInfoSets that maybe included in the list may be 8. Depending on a need of the network, alist of a number of UAC-BarringInfoSet within a maximum number may bebroadcast.

Barring configuration information of each PLMN may be included in aUAC-BarringPerPLMN 2 d-10. The UAC-BarringPerPLMN may largely includeplmn-IdentityIndex 2 d-15 that is identification information indicatingthe PLMN and uac-ACBarringListType 2 d-20 that includes the barringconfiguration information. A structure for including the barringconfiguration information may be divided into uac-ImplicitACBarringList2 d-25 and uac-ExplicitACBarringList 2 d-30. When the number of accesscategories requiring barring check is greater than or equal to aspecific value, uac-ImplicitACBarringList may be useful in terms ofsignaling overhead; otherwise, uac-ExplicitACBarringList may be usefulin terms of signaling overhead. The eNB may broadcast barringconfiguration information by selecting one of structures according towhether the number of a total of access categories requiring barringcheck is greater than or equal to a particular value or the amount ofbarring configuration information is greater than or equal to a specificvalue. Referring to each signaling structure, one index value,usa-barringInfoSetIndex 2 d-40, of UAC-BarringInfoSet for all valid(defined) access categories is sequentially included inuac-ImplicitACBarringList according to an access category number. On theother hand, an indicator indicating an access category, accessCategory 2d-50, for access categories requiring barring check andUAC-BarringPerCat 2 d-45 including one index valueuac-barringInfoSetIndex 2 d-55 among UAC-BarringInfoSet may be includedin uac-ExplicitACBarringList. One UAC-BarringPerCat may correspond toone access category.

A description will be made of a method of configuringuac-barringInfoSetIndex for an access category for which an access isallowed without requiring barring check in a uac-ImplicitACBarringListstructure in an embodiment of the disclosure. The eNB may apply one ofthe following options for indicating the access category for which anaccess is allowed without barring check to the access category.

Option 1) Predefined UAC-BarringInfoSetIndex is mapped and the indexvalue indicates that an access is allowed. For example, among a total of8 uac-barringInfoSetIndex, the smallest index value or the largest indexvalue may be used to indicate no barring. UAC-BarringInfoSet mapped toan index may not be provided or may be regarded as a dummy.

Option 2) UAC-BarringInfoSetIndex that does not correspond to anyUAC-BarringInfoSet is mapped. The index value having no correspondingUAC-BarringInfoSet is regarded as indicating no barring.

Option 3) UAC-BarringInfoSetIndex corresponding to UAC-BarringInfoSetincluding an indicator indicating that an access is allowed or withoutincluding any information is mapped. Although an UAC-BarringInfoSet IEmapped to an index exists, uac-BarringFactor, uac-BarringTime, anduac-BarringForAccessIdentity that are generally included inUAC-BarringInfoSet are not included in UAC-BarringInfoSet. Instead, anindicator indicating no barring may be included, or any information maynot be included.

Option 4) New 1-bit information indicating no barring is further definedin uac-BarringForAccessIdentity information in the form of a bitmap.uac-BarringForAccessIdentity included in UAC-BarringInfoSetcorresponding to UAC-BarringInfoSetIndex to be used for indicating nobarring may have 1-bit information that is set to 0 indicating nobarring. The uac-BarringForAccessIdentity information is used toindicate whether an access generally mapped to an access identity (andemergency) is allowed. Additionally, when new bit information is set tono barring, UAC-BarringInfoSet may not include a uac-BarringFactor fieldand a uac-Barringtime field.

FIG. 17 illustrates a flowchart of operations of a gNB according to anembodiment of the disclosure.

In operation 2 e-05, the gNB may determine whether a total number ofaccess categories requiring barring check is greater than or equal to aspecific value. The gNB may determine whether the amount of barringconfiguration information of the access categories is greater than orequal to a specific value.

In operation 2 e-10, when the gNB may configureuac-ImplicitACBarringList when a total number of access categoriesrequiring barring check is greater than or equal to a specific value.

In operation 2 e-15, the gNB may map UAC-BarringInfoSetIndex to allaccess categories of the gNB.

In operation 2 e-20, the gNB may apply one of the following options forindicating the access category for which an access is allowed withoutbarring check to the access category.

Option 1) Predefined UAC-BarringInfoSetIndex is mapped and an indexvalue indicates that an access is allowed.

Option 2) UAC-BarringInfoSetIndex that does not correspond to anyUAC-BarringInfoSet may be mapped.

Option 3) UAC-BarringInfoSetIndex corresponding to UAC-BarringInfoSetincluding an indicator indicating that an access is allowed or withoutincluding any information is mapped. uac-BarringFactor, uac-BarringTime,and uac-BarringForAccessIdentity that are generally included inUAC-BarringInfoSet are not included in UAC-BarringInfoSet.

Option 4) New 1-bit information indicating no barring is further definedin uac-BarringForAccessIdentity information in the form of a bitmap.uac-BarringForAccessIdentity included in UAC-BarringInfoSetcorresponding to UAC-BarringInfoSetIndex to be used for indicating nobarring may have 1-bit information that is set to 0 indicating nobarring. The uac-BarringForAccessIdentity information is used toindicate whether an access generally mapped to an access identity (andemergency) is allowed. Additionally, when new bit information is set tono barring, UAC-BarringInfoSet may not include a uac-BarringFactor fieldand a uac-Barringtime field. For the other access categories requiringbarring check, one UAC-BarringInfoSetIndex corresponding toUAC-BarringInfoSet including uac-BarringFactor, uac-BarringTime, anduac-BarringForAccessIdentity may be mapped.

In operation 2 e-25, for all access categories, all the mapped indexinformation may be included in uac-ImplicitACBarringList.

In operation 2 e-30, otherwise, the gNB may configureuac-ExplicitACBarringList.

In operation 2 e-35, the gNB may map one UAC-BarringInfoSetIndexcorresponding to UAC-BarringInfoSet including an ID (index value)indicating an access category, and uac-BarringFactor, uac-BarringTime,and uac-BarringForAccessIdentity for the access categories requiringbarring check.

In operation 2 e-40, the gNB may include information mapped to eachaccess category to UAC-BarringPerCat and values of UAC-BarringPerCat ofthe access categories to uac-ExplicitACBarringList.

In operation 2 e-45, the gNB may include the configureduac-ImplicitACBarringList or uac-ExplicitACBarringList to a SIB andbroadcast the SIB.

FIG. 18 illustrates a flowchart of operations of a UE according to anembodiment of the disclosure.

In operation 2 f-05, the UE may receive the SIB broadcast from the gNBand store the received SIB. The SIB may include baring configurationinformation.

In operation 2 f-10, the UE may trigger an access corresponding to oneaccess category. The access may be triggered by the UE NAS or AS.

In operation 2 f-15, the UE may determine whether uac-ACBarringListTypeof the barring configuration information is uac-ImplicitACBarringList oruac-ExplicitACBarringList.

In operation 2 f-20, when uac-ACBarringListType isuac-ImplicitACBarringList, the UE may not perform barring check for anaccess category corresponding to the following options and regard anaccess as being allowed.

Option 1) access category mapped to predefined UAC-BarringInfoSetIndexindicating that an access is allowed.

Option 2) access category mapped to UAC-BarringInfoSetIndex that doesnot correspond to any UAC-BarringInfoSet.

Option 3) access category mapped to UAC-BarringInfoSetIndexcorresponding to UAC-BarringInfoSet including an indicator indicatingthat an access is allowed or without including any information.

In operation 2 f-25, when uac-ACBarringListType isuac-ExplicitACBarringList, the UE may not perform barring check for anaccess category having no corresponding UAC-BarringPerCat and may regardan access as being allowed.

In operation 2 f-30, when an access for an access category other thanthe access category for which the access is allowed is triggered, the UEmay perform baring check for the access, by using stored barringconfiguration information.

In operation 2 f-35, when the access is allowed as a result of barringcheck, the UE may perform connection for the access.

In operation 2 f-40, when the access is not allowed as the result ofbarring check, the UE may delay connection for the access for a specifictime.

FIG. 19 illustrates a block diagram of a structure of a UE according toan embodiment of the disclosure.

Referring to FIG. 19, the UE may include a radio frequency (RF)processor 2g-10, a baseband processor 2 g-20, a storage unit 2 g-30, anda controller 2 g-40.

The RF processor 2 g-10 performs a function for transmitting andreceiving a signal through a wireless channel, such as band translation,amplification, and so forth. That is, the RF processor 2 g-10up-converts a baseband signal provided from the baseband processor 2g-20 into an RF band signal, transmits the RF band signal through anantenna, and down-converts an RF band signal received through theantenna into a baseband signal. For example, the RF processor 2 g-10 mayinclude a transmission filter, a reception filter, an amplifier, amixer, an oscillator, a DAC, an ADC, and so forth. Although one antennais illustrated in FIG. 20, the UE may also include multiple antennas.The RF processor 2 g-10 may include multiple RF chains. The RF processor2 g-10 may perform beamforming. For the beamforming, the RF processor 2g-10 may adjust phases and magnitudes of signals transmitted andreceived through multiple antennas or antenna elements. The RF processor2 g-10 may also perform MIMO and may receive several layers whenperforming MIMO operations.

The baseband processor 2 g-20 performs conversion between a basebandsignal and a bitstream according to physical layer standards of asystem. For example, in data transmission, the baseband processor 2 g-20may generate complex symbols by encoding and modulating a transmissionbitstream. In data reception, the baseband processor 2 g-20 may recovera received bitstream by demodulating and decoding the baseband signalprovided from the RF processor 2 g-10. For example, when OFDM is used,in data transmission, the baseband processor 2 g-20 may generate complexsymbols by encoding and modulating a transmission bitstream, map thecomplex symbols to subcarriers, and construct OFDM symbols through IFFTand CP insertion. Also, in data reception, the baseband processor 2 g-20divides the baseband signal provided from the RF processor 2 g-10 in theunit of an OFDM symbol, recovers the signals mapped to the subcarriersthrough FFT, and recovers the received bitstream through demodulationand decoding.

The baseband processor 2 g-20 and the RF processor 2 g-10 transmit andreceive a signal as described above. Thus, the baseband processor 2 g-20and the RF processor 2 g-10 may be indicated by a transmitter, areceiver, a transceiver, or a communicator. Moreover, at least one ofthe baseband processor 2 g-20 or the RF processor 2 g-10 may includemultiple communication modules for supporting multiple differentwireless connection techniques. In addition, at least one of thebaseband processor 2 g-20 or the RF processor 2 g-10 may includemultiple communication modules for processing signals in differentfrequency bands. For example, the different radio access technologiesmay include a wireless LAN (e.g., IEEE 802.11), a cellular network(e.g., LTE), and the like. In addition, the different frequency bandsmay include a super high frequency (SHF, e.g., 2.5 GHz, 5 GHz) band, anda millimeter wave (mm-wave, e.g., 60 GHz) band.

The storage unit 2 g-30 stores data such as a basic program foroperations of the UE, an application program, configuration information,and so forth. The storage unit 2 g-30 provides the stored data at therequest of the controller 2 g-40.

The controller 2 g-40 controls overall operations of the UE. Forexample, the controller 2 g-40 may transmit and receive a signal throughthe baseband processor 2 g-20 and the F processor 2 g-10. The controller2 g-40 records and reads data from and in the storage unit 2 g-30. Tothis end, the controller 2 g-40 may include at least one processor.According to an embodiment of the disclosure, the controller 2 g-40includes a multi-connection processor 2 g-42 configured to performprocessing to operate in a multi-connection mode. For example, thecontroller 2 g-40 may control the UE of FIG. 2g -42 to perform aprocedure of operations of the UE. For example, the controller 2 g-40may include a CP for performing control for communication and an AP forcontrolling a higher layer such as an application program.

FIG. 20 illustrates a block diagram of a structure of an eNB accordingto an embodiment of the disclosure.

As shown in FIG. 20, the eNB may include an RF processor 2 h-10, abaseband processor 2 h-20, a backhaul communicator 2 h-30, a storageunit 2 h-40, and a controller 2 h-50.

The RF processor 2 h-10 may perform a function for transmitting andreceiving a signal through a wireless channel, such as band translation,amplification, and so forth. That is, the RF processor 2 h-10up-converts a baseband signal provided from the baseband processor 2h-20 into an RF band signal, transmits the RF band signal through anantenna, and down-converts an RF band signal received through theantenna into a baseband signal. For example, the RF processor 2 h-10 mayinclude a transmission filter, a reception filter, an amplifier, amixer, an oscillator, a DAC, an ADC, and so forth. Although one antennais illustrated in FIG. 20, the UE may also include multiple antennas.The RF processor 2 h-10 may include multiple RF chains. The RF processor2 h-10 may perform beamforming. For the beamforming, the RF processor 2h-10 may adjust phases and magnitudes of signals transmitted andreceived through multiple antennas or antenna elements. The RF processor2 h-10 may perform downward MIMO operations by transmitting one or morelayers.

The baseband processor 2 h-20 performs conversion between a basebandsignal and a bitstream according to physical layer standards of asystem. For example, in data transmission, the baseband processor 2 h-20may generate complex symbols by encoding and modulating a transmissionbitstream. In data reception, the baseband processor 2 h-20 may recovera received bitstream by demodulating and decoding the baseband signalprovided from the RF processor 2 h-10. For example, when OFDM is used,in data transmission, the baseband processor 2 h-20 may generate complexsymbols by encoding and modulating a transmission bitstream, map thecomplex symbols to subcarriers, and construct OFDM symbols through IFFTand CP insertion. Also, in data reception, the baseband processor 2 h-20divides the baseband signal provided from the RF processor 2 h-10 in theunit of an OFDM symbol, recovers the signals mapped to the subcarriersthrough FFT, and recovers the received bitstream through demodulationand decoding. The baseband processor 2 h-20 and the RF processor 2 h-10transmit and receive a signal as described above. Thus, the basebandprocessor 2 h-20 and the RF processor 2 h-10 may be indicated by atransmitter, a receiver, a transceiver, a communicator, or a wirelesscommunicator.

The backhaul communicator 2 h-30 provides an interface for performingcommunication with other nodes in a network. That is, the backhaulcommunicator 2 h-30 converts a bitstream transmitted to another node,e.g., an auxiliary eNB, a core network, etc., into a physical signal,and converts a physical signal received from the another node into abitstream.

The storage unit 2 h-40 stores data such as a basic program foroperations of the main eNB, an application program, configurationinformation, and so forth. In particular, the storage unit 2 h-40 storesinformation about a bearer allocated to the connected UE, and ameasurement result reported from the connected UE. The storage unit 2h-40 stores information that is a criterion for determining whether toprovide or stop multiple connections to the UE. The storage unit 2 h-40provides the stored data at the request of the controller 2 h-50.

The controller 2 h-50 controls overall operations of the main eNB. Forexample, the controller 2 h-50 may transmit and receive a signal throughthe baseband processor 2 h-20 and the RF processor 2 h-10 or through thebackhaul communicator 2 h-30. The controller 2 h-50 records and readsdata from and in the storage unit 2 h-40. To this end, the controller 2h-50 may include at least one processor. According to an embodiment ofthe disclosure, the controller 2 h-50 includes a multi-connectionprocessor 2 h-52 configured to perform processing to operate in amulti-connection mode.

The methods according to the embodiments of the disclosure described inthe claims or specification of the disclosure may be implemented byhardware, software, or a combination thereof.

When the methods are implemented by software, a computer-readablestorage medium or a computer program product having stored therein oneor more programs (software modules) may be provided. The one or moreprograms stored in the computer-readable storage medium or computerprogram product may be configured for execution by one or moreprocessors in an electronic device. The one or more programs includeinstructions that cause the electronic device to execute the methodsaccording to the embodiments of the disclosure described in the claimsor the specification of the disclosure.

These programs (software modules and software) may be stored in randomaccess memories (RAMs), non-volatile memories including flash memories,read only memories (ROMs), electrically erasable programmable ROMs(EEPROMs), magnetic disc storage devices, compact disc-ROMs (CD-ROMs),digital versatile discs (DVDs), other types of optical storage devices,or magnetic cassettes. The programs may be stored in a memory configuredby a combination of some or all of such storage devices. Also, each ofthe memories may be provided in plurality.

The programs may be stored to an attachable storage device of theelectronic device accessible via the communication network such asInternet, Intranet, a local area network (LAN), a wireless LAN (WLAN),or storage area network (SAN), or a communication network by combiningthe networks. The storage device may access a device performing theembodiment of the disclosure through an external port. Furthermore, aseparate storage device in a communication network may access a deviceperforming the embodiment of the disclosure.

According to disclosed embodiments of the disclosure, a service may beeffectively provided in a mobile communication system.

In the detailed embodiments of the disclosure, components included inthe disclosure have been expressed as singular or plural according tothe provided detailed embodiment of the disclosure.

In an embodiment of the disclosure, the parameters UAC-BarringInfoSet,UAC-BarringInfosetList, uac-BarringPerPLMN, uac-BarringPerPLMN-List,uac-BarringInfo, and BarringInfoSetIndex may be expressed as barringsetting information, a barring setting information list, barringinformation per PLMN, a PLMN-specific barring information list, barringinformation, and a barring configuration information index,respectively.

The parameters plmn-IdentityIndex, uac-ACBarringListType,uac-ImplicitACBarringList, uac-ExplicitACBarringList, accessCategory,and UAC-BarringPerCat may be expressed as a PLMN ID index, barring listtype information, an implicit barring list, an explicit barring list,access category information, and category-specific barring information,respectively. However, singular or plural expressions have been selectedproperly for a condition provided for convenience of a description, andthe disclosure is not limited to singular or plural components andcomponents expressed as plural may be configured as a single componentor a component expressed as singular may also be configured as pluralcomponents.

Meanwhile, the embodiments of the disclosure of the presentspecification and drawings have been provided to easily describe thedisclosure and to help with the understanding of the disclosure, and arenot intended to limit the scope of the disclosure. In other words, it isapparent to one of ordinary skill in the art that various changes may bemade thereto without departing from the scope of the disclosure. Inaddition, the embodiments of the disclosure may be used in combinationwhen necessary. For example, an embodiment of the disclosure may becombined with some parts of another embodiment of the disclosure. Inaddition, other modifications based on the technical spirit of theabove-described embodiment of the disclosure may also be carried out inother systems, e.g., an LTE system, a 5G system, an NR system, etc.

Although the present disclosure has been described with variousembodiments, various changes and modifications may be suggested to oneskilled in the art. It is intended that the present disclosure encompasssuch changes and modifications as fall within the scope of the appendedclaims.

What is claimed is:
 1. A method, performed by a user equipment (UE), ofcontrolling an access, the method comprising: receiving, through systeminformation from a base station, barring information comprising abarring configuration information list and a public land mobile network(PLMN)-specific barring information list, the barring configurationinformation list comprising at least one barring configurationinformation and the PLMN-specific barring information list comprising atleast one barring information per PLMN; and performing a barring checkbased on the received barring information when the access is triggered,wherein the barring configuration information corresponds to one barringconfiguration information index according to an order of being includedin the barring configuration information list.
 2. The method of claim 1,wherein: the barring information per PLMN comprises a PLMNidentification (ID) index and barring list type information; and theperforming of the barring check comprises: in response to the barringlist type information indicating an implicit barring list, performingthe barring check based on barring configuration informationcorresponding to the barring configuration information index mapped tothe triggered access included in the implicit barring list.
 3. Themethod of claim 2, further comprising determining to allow the accesswithout performing the barring check, when there is no barringconfiguration information corresponding to the barring configurationinformation index mapped to the triggered access.
 4. The method of claim2, wherein: an explicit barring list comprises at least onecategory-specific barring information, each category-specific barringinformation comprising access category information and the barringconfiguration information index; and the performing of the barring checkcomprises: in response to the barring list type information indicatingthe explicit barring list, performing the barring check based on barringconfiguration information corresponding to the barring configurationinformation index for the access category information corresponding tothe triggered access.
 5. The method of claim 1, wherein a maximum numberof barring configuration information able to be included in the barringconfiguration information list is
 8. 6. The method of claim 1, whereinthe barring configuration information comprises barring informationregarding a barring factor, a barring time, and an access identity. 7.The method of claim 1, further comprising receiving, through anoperations, administration, and maintenance (OAM) message or anon-access stratum (NAS) message from the base station, informationregarding an operator-specific access category, wherein the performingof the barring check comprises: triggering the access; mapping thetriggered access to an access identity and an access category based oninformation about the information regarding the operator-specific accesscategory; and performing the barring check based on the access identityand the access category.
 8. The method of claim 1, further comprisingdelaying the access when the access is not allowed according to thebarring check.
 9. A method, performed by a base station, of controllingan access in a mobile communication system, the method comprising:determining whether to use an implicit barring list or an explicitbarring list, based on a preset criterion; generating the implicitbarring list comprising at least one barring configuration informationindex corresponding to at least one access category when determining touse the implicit barring list, or generating the explicit barring listcomprising at least one category-specific barring information, eachcategory-specific barring information comprising access categoryinformation and the at least one barring configuration information indexwhen determining to use the explicit barring list; and broadcasting,through system information, barring information comprising a barringconfiguration information list, the barring configuration informationlist comprising at least one barring configuration information, thebarring information further comprising at least one of the implicitbarring list or the explicit barring list, wherein the barringconfiguration information corresponds to one barring configurationinformation index according to an order of being included in the barringconfiguration information list.
 10. The method of claim 9, furthercomprising generating the implicit barring list by mapping a barringconfiguration information index that is not mapped to the barringconfiguration information, to an access-allowed access category withoutperforming the barring check, when determining to use the implicitbarring list.
 11. A user equipment (UE) controlling an access in amobile communication system, the UE comprising: a communication unit;and a controller configured to: receive, through system information froma base station, barring information comprising a barring configurationinformation list and a public land mobile network (PLMN)-specificbarring information list, the barring configuration information listcomprising at least one barring configuration information and thePLMN-specific barring information list comprising at least one barringinformation per PLMN, and perform a barring check based on the receivedbarring information when the access is triggered, wherein the barringconfiguration information corresponds to one barring configurationinformation index according to an order of being included in the barringconfiguration information list.
 12. The UE of claim 11, wherein: thebarring information per PLMN comprises a PLMN identification (ID) indexand barring list type information; and the controller is configured to:in response to the barring list type information indicating an implicitbarring list, perform the barring check based on barring configurationinformation corresponding to the barring configuration information indexmapped to the triggered access among at least one barring configurationinformation index included in the implicit barring list.
 13. The UE ofclaim 12, wherein the controller is further configured to determine toallow the access without performing the barring check, when there is nobarring configuration information corresponding to the barringconfiguration information index mapped to the triggered access.
 14. TheUE of claim 12, wherein: an explicit barring list comprises at least onecategory-specific barring information, each category-specific barringinformation comprising access category information and the barringconfiguration information index; and the controller is furtherconfigured to: in response to the barring list type informationindicating the explicit barring list, perform the barring check based onbarring configuration information corresponding to the barringconfiguration information index for the access category informationcorresponding to the triggered access.
 15. The UE of claim 11, wherein amaximum number of barring configuration information able to be includedin the barring configuration information list is
 8. 16. The UE of claim11, wherein the barring configuration information comprises barringinformation regarding a barring factor, a barring time, and an accessidentity.
 17. The UE of claim 11, wherein the controller is furtherconfigured to: receive, through an operations, administration, andmaintenance (OAM) message or a non-access stratum (NAS) message from thebase station, information regarding an operator-specific accesscategory; trigger the access; map the triggered access to an accessidentity and an access category based on information about theinformation regarding the operator-specific access category; and performthe barring check based on the access identity and the access category.18. The UE of claim 11, wherein the controller is further configured todelay the access when the access is not allowed according to the barringcheck.
 19. A base station controlling an access in a mobilecommunication system, the NB comprising: a communication unit; and acontroller configured to: determine whether to use an implicit barringlist or an explicit barring list, based on a preset criterion, togenerate the implicit barring list comprising at least one barringconfiguration information index corresponding to at least one accesscategory when determining to use the implicit barring list, or togenerate the explicit barring list comprising at least onecategory-specific barring information, each category-specific barringinformation comprising access category information and the at least onebarring configuration information index when determining to use theexplicit barring list, and broadcast, through system information,barring information comprising a barring configuration information list,the barring configuration information list comprising at least onebarring configuration information, the barring information furthercomprising at least one of the implicit barring list or the explicitbarring list, wherein the barring configuration information correspondsto one barring configuration information index according to an order ofbeing included in the barring configuration information list.
 20. The NBof claim 19, wherein the controller is further configured to generatethe implicit barring list by mapping a barring configuration informationindex that is not mapped to the barring configuration information, to anaccess-allowed access category without performing the barring check,when determining to use the implicit barring list.